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Stay cozy and comfortable with our collection of warm undergarments designed for ultimate insulation and softness. Crafted from high-quality, moisture-wicking materials, these essentials provide the perfect base layer for any cold-weather activity. Whether you're layering up for outdoor adventures or simply seeking extra warmth at home, our selection offers a variety of styles and fits to suit your needs. Experience the perfect blend of functionality and comfort, ensuring you stay warm without sacrificing style. Embrace the chill with confidence in our premium warm undergarments.
$55.00
Wonderfully made and kept me warm. ... Wear them under my work pants and they help me stay warm ... This is so warm! ... I love that they are high wasted and a large
5
Jeff48
Wonderfully made and kept me warm. Well fitting and comfortable.
5
Mars Go
This is so warm! It is surprising
5
Brydollaz
Fits great. Soft fitted material protects from the cold. Wear them under my work pants and they help me stay warm
5
JofD
UA leggings are of great quality, fit, and comfortable.
5
happycusstomer
I had an old pair of cold gear leggings from under armour gifted to me by a friend around 2010. I 've been looking for a new pair to add to my rotation and these did not disappoint. Super comfy. I typically wear a size 4- 6 in pants and went with a medium. Not too compressive but fit great at the waist( 27 '').
$19.99
WAS: $24.99*
Helped to keep me warm ... Warm and comfy ... Keeps me warm, does n't ride up( great fit) and super soft! ... Very Comfortable ... I bought one last year and liked it enough that I decided to buy another
5
DreaV
Keeps me warm, does n't ride up( great fit) and super soft!
5
Conn
Wore it to an outdoor activity in NY in November! Helped to keep me warm
5
Beach Lover
I bought one last year and liked it enough that I decided to buy another one.
4
Moon
Fits well, feels really good, washes well. I 'd recommend.
$40.00
These pants keep me warm in class and then on the ride home. ... They are warm enough to work on cold days in New England and the fabric is high quality. ... Great on its own or under a pair of jeans for extra
5
emykaboom
Great on its own or under a pair of jeans for extra warmth. Comfortable and light weight for an active boy
5
K8Eo
Are they strictly for cooler temps, as it will warm up here in a month
5
Football Grammie
I buy my grandson his football clothing from here every year. Never disappointed!!!
5
Hockey mom 2021
[ Ordered this one for my son who is playing hockey. This is definitely the most comfortable and This is definitely the most comfortable and versatile piece of workout apparel that he own. My son likes it so much.
5
SwimmrMama
[ My son lives in these leggings with shorts layered over year round. They are warm enough to work on cold days in New England and the fabric is high quality. Wish they were a little longer but otherwise can ’ t be beat!
$54.99
Very Warm, Comfortable Thermal Pants ... This is an awesome base layer pant for cold temps and winter weather very warming but not restrictive ... These my friends are warm comfy and above all just comfortable not to tight not to loose, and...
5
Robert
Bought these to use as an alternative to fleece lined work pants. Much prefer these as it provides more flexibility, yet keeps you warm. They fit well and pair with my canvas work pants. I particularly like the idea that if the weather warms up enough, I can simply take them off, whereas with lined pants, you 're stuck unless you keep an additional pair of pants with you. These launder well too. The seams in them are placed well so there's no `` tugging '' or tightness. To me, they 're a great cold weather investment.
5
RonaldR
[ Really good and very warm comfortable insulated pants.
5
ToddS
Had the chance to trial these on a field test, very warm and durable. nice snug fit, plenty of room to flex and move. No need for extra layers with these, wore with Carhartt lined bibs and was very comfortable all day
5
DanielF
I received this set of base layer pants for a Carhartt Crew Filed Test to test its warmth, comfort, and durability in real world working conditions. This is by far the warmest and most comfortable set of base layer pants I have ever worn. I wore them over the winter in Colorado and Wyoming in cold weather, heavy snow, and strong winds. I was warm and comfortable no matter what Mother Nature threw at me. They wick away moisture and move with me all day. I would recommend this base layer for anyone who works outdoors in the winter.
5
PatrickK
Received these thermal pants for Carhartt field testing. They strike a nice balance between being very warm, lightweight, and comfortable. Wore under double- front jeans or canvas pants in single- digit temperatures with negative wind chills and my legs stayed warm while moving/working. Their light weight is nice for putting in a pack if it gets too warm while hunting or hiking. They are also comfortable to lounge in in warmer temperatures! Pants are true to size and seem durable, however, I have heard thread stretching when I put them on from time to time( I wear size large and am between a 34- 36 waist).
$44.99
They fit great and keep me nice and warm working outside in the wind all day. ... Keep Warm ... Keeps me warm in 30 degree weather with gusts, and matches the same style top baselayer
5
Cynthia
[ My husband said he will never wear anything else since buying these he ’s in love with them!
5
JustinK
[ very nice product here. Keeps me warm in 30 degree weather with gusts, and matches the same style top baselayer well. Overall great buy.
5
EricG
Very comfortable and warm without being too bulky underneath a pair of jeans. Highly recommend!
5
LantzW
Easy to put on great fit and feel
5
Rico 51
I bought these a month ago and absolutely pleased with the quality going back to buy two more and they do keep you warm.
$115.00-$125.00
Went skiing at altitude with this as my base layer and it kept me incredibly warm! ... It's a great color and it's comfortable. ... Perfect base layer! ... My husband loves
5
Just another white guy
Went skiing at altitude with this as my base layer and it kept me incredibly warm!
5
Enjoy
My husband loves it. It's a great color and it's comfortable.
$159.99
They 're very warm and comfortable to wear when I take a walk. ... I love these base liner pants they are very warm, and I am a person that is always cold. ... They kept me warm during cold skiing
5
Camille
I am a journalist and used to go to places where it always get my feet cold, I 've tried looking for alternatives to keep my feet, torso and my knees warm. Until I found out about this product and tried, it never failed. I ordered some socks too. Thanks
5
Rosemary
I love these base liner pants they are very warm, and I am a person that is always cold. I am so thankful that I decided to buy these.
5
A E.
I am so glad I purchased these pants. They kept me warm during cold skiing days! I bought size xs, and it fits ok, just a tiny bit too lose.( I wear jeans size 25 or 26, and I am 5' 7 ''/ 120lb)
5
Susan
These pants were very warm and well made. The only thing wrong is they run big. i normally wear a size medium in everything and these were too big in medium and had to reorder in small.
5
Candance
These pants are awesome. I am a rancher and I need all the heat I can get. This product fits the bill.
$65.00
I ’ m always cold so these are a blessing for me because they keep me warm and they are not bulky. ... Keeps you warm ... They keep me warm in the coldest
5
Zay63
These are great! They keep me warm in the coldest weather. I ’ m always cold so these are a blessing for me because they keep me warm and they are not bulky. They wash up great.
5
Monkmpd
By far the best and warmest product you can buy. The sizing accurate. Spend the money and buy this instead of the cheaper, knock offs that do not perform as well.
5
Britt829
These are amazing! We love them. ❤️ My dad got my husband and I both a set for Christmas like 10 years ago or more. They are still in perfect condition. We use them for hunting, playing in the snow or anytime we have to be outside for long periods of time in the cold. When I go hunting and it's super cold or wind chill of- 15. I wear mine, my husband's and my under armour sweat pants under my hunting bibs. No need for a heater at all. My son told me he needed some bigger under layers so I automatically ordered him this set. He is going to be so excited when he gets the Christmas morning. If you have multiple children you definitely need to get these. They are such a good quality and will last for years if they are taken care of. The adults sizes are pretty unisex in the bottoms. The woman's top seems to be a little more fitted for the breast.
5
Under armour pants
Fits my grandson he can wear them for indoor practice during winter then outside in spring
$57.99
These Undergarments were a gift to my son. ... He is very satisfied, says this helps keep him warm better than other brands he has tried. ... Comfortable and
5
AntonS
Super warm. Perfect size and fit. Would definitely buy again.
5
MarvinW
[ Makes an excellent base layer for outdoor sports activity. Just used mine on a ski trip in very cold weather and it was perfect. I wont hesitate to buy more of the CARHARTT base layer product line.
5
SusanE
These Undergarments were a gift to my son. He wears them daily and he says they are great. They keep him warm and I 'm going to order more for him un the future. I would definitely recommend these to my other 3 sons and anyone else who is looking for the same type of clothing. Thank you Carhartt... excellence always!
5
SurfinSquatch
[ Bought it just in time for winter construction work. Keeps me warm and is comfortable all day. It ’s very durable and is a great addition to any cold weather wardrobe.
5
cse04
Bought for my husband who works outside for 12+ hours a day. He is very satisfied, says this helps keep him warm better than other brands he has tried.
$125.00
Perfect weight to stay warm in cold weather. ... I love how they keep me warm but do n't make me hot. ... He said the fit was true to size and they kept him warm while snowmobiling and
5
tjflan2
Fit true and worked outstanding as base layer for football game. Very comfortable and breathable.
5
Mountain time
Fit great especially in length. Perfect weight to stay warm in cold weather.
5
Kwhendy
Bought these about a week ago and wear them nearly every day. I love how they keep me warm but do n't make me hot.
5
srgmnh
These really are a step above. Great fabric, great warmth, hold their shape well. Worth every penny.
4
Jdub
Smart wool has always made quality products and these are no different. But… awfully pricey for a pair of long Johns!
$54.99
They run warm, so on a cold day, they are perfect. ... It is the perfect weight, feels very comfortable and keeps you warm. ... They were warm without being hot, did not bunch in the crotch, and I had on jeans over
5
ChelseaR
Was absolutely impressed with these! So warm, yet light weight and breathe able. Nice fit and super comfortable!!
5
Mamie90
I am impressed with my Carhartt Poly- wool bottom. I received the thermal as part of a Carhartt Crew Field Test, but I will be ordering two more complete sets. I am truly amazed at how well this bottom works to keep me warm. One must understand, I am constantly cold, so to me, this is amazing. I am 5ft 3in, and weigh 115lbs, and the small works well for me. I have laundered it, with no ill effects. It has retained it's shape and fit very well. The bottom also fits perfectly under skinny jeans, without bunching or showing. I live in Iowa, and it gets cold here. While wearing this pair of thermal bottoms, I stayed warm. It really goes long way in cutting the harsh winds we get out here on the prairie. I can honestly recommend this thermal bottom to anyone who gets cold in the winter.
5
JulieB
I received as part of the Carhartt Crew Field Test. It is the perfect weight, feels very comfortable and keeps you warm. It has a bit of a stretch to it so it easy to move around in. Very good quality. You wo n't be disappointed.
5
ErinB
I received this item as part of the Carhartt Crew Field Test. The fabric is softer than I was expecting and the fit is pretty true to size. They are very warm as an under layer!
5
TeriC
[ These are a really cozy and warm bottom layer for Winter. They run warm, so on a cold day, they are perfect. The waistline band can become bunched from wear and washing so you may need to reposition it after a few washings. Otherwise, a fabulous warm bottom layer that has a soft wool fabric.
$34.99
Thank you. ... Definitely would recommend this Carhartt base layer pant to my friends. ... Great product and great price. ... Happy with my Carhartt waffle base layer, bought the same thing maybe four years ago and loved them, and I still love
$54.99
Great quality, superior warmth, and comfort. ... This material is soft and very warm. ... It most certainly works for a very warm base layer. ... Comfortable and warm, but not
5
Mamie90
I received the thermal heavyweight shirt as part of a Carhartt Crew Field Test, but I can honestly say that this shirt is necessary for everyone living in a cold climate. I find that the sizing is true, and the small works well for me. The shirt handles being laundered very well, without shrinking or pilling. It has retained it's shape. I wash in cool water, and I use fabric softener in addition to laundry soap. The Carhartt heavyweight poly wool shirt is extremely effective in keeping me warm, and blocking the harsh Iowa wind. I tend to stay cold, so this is saying a lot. I love the shirt, because it is fitted. It works well under clothing, without bunching up. I appreciate the `` thumb holes '' on the sleeves, since this prevented the sleeves from riding up while I put on my sweatshirt. Great quality, superior warmth, and comfort.
5
JulieB
I received as part of the Carhartt Crew Field Test. It is the perfect weight, feels very comfortable and keeps you warm. It has a bit of a stretch to it so it easy to move around in. Very good quality. You wo n't be disappointed.
5
ErinB
I received this item as part of the Carhartt Crew Field Test. The fabric is softer than I was expecting and the fit is pretty true to size. They are very warm as an under layer!
5
TeriC
[ Super Comfortable and very warm, these bottoms are a great base layer when it is cold. They keep you warm outside or inside and are very soft wool. They can handle the washing machine and fit well under my jeans or Carhartt twill pants.
5
AshleighP
function> material although I am very particular with the texture of my clothing the purpose outweighs the texture. It most certainly works for a very warm base layer.
$22.97-$44.99
WAS: $44.99*
Definitely recommend to anyone looking for warmth and comfort ... Fits great under clothes and gives you that extra warmth. ... I wore them under my Jean's and tshirt to work and they kept me just the perfect
5
JenniferM
I received this thermal shirt as part of the carhartt crew field test and let me just say they are amazing. The fabric is soft and silky and they fit true to size. I wore them under my Jean's and tshirt to work and they kept me just the perfect warmth. I wear them about 3 times a week and wash them as well and they seem to be holding up great so thank you for a great product. Definitely recommend to anyone looking for warmth and comfort
5
Babyd
I received this thermal shirt to test from carheartt crew and I absolutely love it! It is very comfortable and fits perfectly. I love the moisturizer wicking fabric! It has hidden thumb loops to make it easy to put on your jacket. I would definitely recommend this thermal to family and friends.
5
AndreaJ
I received the Base Force Midweight Tech Crew Thermals as part of a Carhartt Crew field test and I'am so happy I did because I love these thermals! My favorite part is the thumb loopholes that keeps your thermal shirt in place when you layer over top of it with jackets or sweatshirts. The thermal is very comfortable and kept me dry at all times. It has sweat wicking& prevents odor. You can not go wrong with this thermal and I highly recommend it.
5
MELANIEW
I couldn ’ t be happier about being chosen to field test this set! As requested I wore these as much as possible( 3- 4 x a week)! These are honestly the best thermals I ’ ve ever worn!! Whom ever designed these thought of everything!! From the warm ultra soft moisture wicking fabric that keeps you dry and toasty, to the stay in place thumb holes in the top for comfort, you couldn ’ t ask for better thermals!!
5
MehganM
Love the deep purple, top base layer! It fit really well and was long enough despite my 5' 11 '' height. If you are a C cup or bigger, you might want to size up, but for anything smaller it should work. It's odd that this was long enough but the matching pants are not as I 'm very proportional. In any event, I 'm grateful to have this top and I love the feminine color! Thank you!
$159.99
keeps my legs warm under my jeans. ... I wanted some warm longjohns for skiing so I got a pair for xmas. ... This might sound silly but I wear these under my shorts on the way to the gym, and they really keep my legs
5
I work in construction, this product has been great during the colder months! They keep my legs warm, and they are n't constricting. Best of all, I can charge my phone with the powerbank! I would recommend this item to anyone that does n't like being cold( not just people that work in the trades)
5
Derrick
The thin material plus the heating elements are perfect combination for going outside in your favorite jeans
5
V
Used in temps with below zero wind chill. Worked perfectly without making me too hot.
5
Ed
The quality of the bottoms is great. Work outstanding on a cold night ride. Thin material that fits easily beneath my jeans.
5
Danny
This might sound silly but I wear these under my shorts on the way to the gym, and they really keep my legs warm. Great buy
$159.99
I 've only used it so far riding in 50 degree weather but it was warm enough I had to turn it down or off. ... Comfortably Warm ... Absolutely was warmer ... I highly recommend the heated base layer for anyone that spends time outdoors in the...
5
I started with the Action Heat socks, and had to add the base layer to my collection. It ’s just the right amount of heat in the right places to make cold winter hunting trips much more enjoyable. I highly recommend the heated base layer for anyone that spends time outdoors in the winter.
5
Motorcycle C.
I got this primarily for motorcycling in colder weather. It works great. I can wear this with my jacket and jacket liner and I do n't have to wear other layers. I 've only used it so far riding in 50 degree weather but it was warm enough I had to turn it down or off. I usually wear a large but wanted it to fit tighter so I got a medium. The medium fits great. I would say the medium fits me perfect where normally I would wear a large t- shirt or long sleeve. Not too tight but not loose. Have n't had long enough to know how long the battery would last but have used it for a couple hours switching between high and medium and still have battery left. Would definitely use while skiing, etc
5
Laura
Great service and reasonable delivery time, especially as a Christmas order. This base garment is very well made and sizing is perfect. Very pleased.
5
Joshua
I just got my base layer and wore it to walk the dog and it was cold and windy outside. Absolutely was warmer
5
Rodney
Heats your body very well, keeps the cold out, easy to use, must be cleaned gently, I use all the time when a must to be outside for a long duration.
$29.99
Girlfriend says that they kept her warm on the colder days ... Helps keep me warm while I ’ m out coaching on the track. ... Very warm ... Good fit ... Good fit, good
5
Mike 8x6
Girlfriend says that they kept her warm on the colder days
5
Arnie
Bought these for an under layer for work and they ’ re great
5
Betty
Bought to replace a base layer of Winter silks. I really like them.
4
Filipe
Good fit, good price! Helps keep me warm while I ’ m out coaching on the track.
$125.00
This shirt is so soft and warm! ... She loves it- Warm and cozy and fits like a glove! ... It provides enough warmth without being bulky. ... Warm and cozy ... Fits well, comfortable and a breathable but warm base...
5
Track Mom
Material is so soft. It is also thicker than most other brand wool base layer tops I have bought. Smartwool is a great brand.
5
Raka
Fits well, comfortable and a breathable but warm base layer.
5
Valentine56
This shirt is so soft and warm! As a senior citizen, I get cold easily. Wearing this shirt to sleep in keeps me comfortably cozy.
5
LT70
I bought this shirt about a month ago because it was on clearance. I have already used it a few times while cross- country skiing and it is great. It provides enough warmth without being bulky. I am satisfied with my purchase.
5
Mele
[ I bought this for a gift for my daughter who works outside in Oregon winters with the horses. She loves it- Warm and cozy and fits like a glove! great base layer! Smart wool has been my go to for years!
$49.99
Super warm and perfect fit. ... Keeps you warm. ... [ Very warm, comfortable and lightweight. ... They are very comfortable to wear and keep you warm in very cold windy temps as a base layer and are very breathable as I also wore...
5
KKinzler
My husband loves these!! He practically lives in them. When working on the farm you find yourself running in and out of equipment during those cold months. Just a heads up they will shrink if put in dryer!
5
PedroC
[ Does the job! Stitching on item is top shelf. Keeps you warm. What more could I say?
5
AntonS
Super warm and perfect fit. Would definitely buy again.
5
MildredM
[ My grandson loves the feel the fit the comfort of these thermals he also loves the thumb ring at the end of the shirt sleeve he said it's easy to keep it down while he's putting on other layers.
5
JohnnyK
[ Bought them for hunting tried them out over the weekend. The morning temps were about 4* between the base layer and my jacket I was comfortable.
$115.00-$125.00
They are warm for sure but I can ’ t wait until ... It should be comfy and warm. ... Cozy and warm pants ... They are of good quality and very soft and warm. ... They are so soft, warm and
5
Maw maw Z
My legs will not be cold this winter. They are of good quality and very soft and warm.
5
Tara H.
Absolutely love the feel of these thermal pants. I plan to use these on the trail to sleep in on cold nights. It should be comfy and warm. Can ’ t wait.
5
Tara H.
I absolutely love the Smart Wool Thermal merino wool leggings- will be using the set to sleep in for colder hike thrus this fall up north. I can ’ t wait. They are so soft, warm and comfy. The fit was great and I really like the color.
5
Sydroo
Fits true to size. Keeps you warm! Relaxed fit and love the color. Makes snowboarding more enjoyable.
5
Mim1
Used these under sweats in below freezing temperatures in Quebec City sometimes needed snow pants too, other times just the two layers.
$120.00
Longer than anticipated but probably good for tucking in, though not the look I wanted. ... Nice quality, runs
$130.00-$150.00
[ This is a quality built base layer and I 've worn it by itself or under a light jacket for plenty of warmth. ... [ Feels light on the skin and is plenty
5
MoosejawDon
[ Feels light on the skin and is plenty warm. I would like a little more move/breath ability in the pits however I do not feel sweaty. Perfect base or mid layer
5
Timoby2k
[ This has become my new favorite baselayer. It ’s form fitting and the multi panels really make it articulate with my movements. I wear it as my only layer in damp mid thirty degree runs. Also looks good to wear on its own out and about.
4
Rory
[ This is a quality built base layer and I 've worn it by itself or under a light jacket for plenty of warmth. Be advised to go one size up, especially if you have an athletic muscular build. Fits close to skin, athletic cut for sure. Looks awesome.
$130.00-$150.00
It provides a warm, yet breathable layer under my light down jacket. ... Keeps me warm, yet comfortable when exercising ... [ This sweater is super lightweight and
5
G Love
[ This top made me ski like an olympiad. Really, it's that good, so I 'm buying it in navy. My favorite underlayer by a long shot, I literally wore it every day of my last ski trip- 5 days in a row. Shhhh.
5
Jess13
[ I bought this about 3 weeks ago… to keep me warm on a climbing trip where we would encounter cooler weather! I have dressed it up, wore around the cabin and out for hikes. I highly recommend!
5
Laurie
[ I bought this several weeks ago and have worn it on several chilly( and hilly) NE dog walks. It provides a warm, yet breathable layer under my light down jacket. It fits very close to my body and adds very little bulk. I appreciate the generous sleeve length. I have yet to launder it as I wear it as a middle layer.
5
Lisa W.
I love this shirt. I had two others that I stained and needed to replace. Thank you.
5
Bouldergirl
[ This is my favorite top for hiking. It is the perfect weight and is useful all year round! I wear it's a base layer in winter and a top layer in summer for cooler days. Best material ever!
$120.00-$145.00
And amazingly the fabric keeps your body temperature warm yet it allows it to breathe with changing temps to create a perfect balance of core
5
Kevin C.
Excellent slim fit. Love that you can wear with shorts or pants, hiking and nice to wear out with friends. Very comfortable while keeping your core temperature comfortable.
5
Matt K.
I bought this Hoodie for a cold weather trip in the fall. Great fit& style. ove the black with gold contrast. It's a great base layer and will hardly takeup any carry- on room. Great produt from SmartWool!
5
Kevin C.
Absolutely love the lightweight fit and comfortability. It fits true to size. This is my fourth purchase of this line. Each has been exactly the same in fit and comfort. And amazingly the fabric keeps your body temperature warm yet it allows it to breathe with changing temps to create a perfect balance of core temperature.
5
Jeff D.
I live in the northeast part of the country and the climate is cold in the winter. I love my Smartwool base layers. I have had earlier versions of this base layer and I was able to get a newer version on sale( lucky me!!!). I tried it on and the material is super soft and comfortable.
5
Joseph M.
This is the best mid weight zip neck base layer I ’ ve ever owned. The quality of the fabric is unmatched. I ’ ve never had a Smartwool garment that pilled. It looks good enough to wear as a shirt/sweater. The zipper is first class and the neck doesn ’ t sag. I were it as a base layer skiing all over the IS and Canada, cycling in cold weather, and under a shirt all winter to take the North Atlantic chill of fall through spring. Best of all I can wear it without worrying about the dreaded polyester stink, its stays fresh for ages.
Warm undergarments are typically made from a variety of materials designed to provide insulation and moisture-wicking properties. Common fabrics include synthetic blends, merino wool, and polyester, which help retain body heat while allowing sweat to escape. These materials are chosen for their ability to keep you warm without adding bulk.
When selecting warm undergarments for outdoor activities, consider the climate and the intensity of your activity. Look for options that offer a snug fit to trap heat while still allowing for movement. Additionally, prioritize moisture-wicking fabrics to keep you dry and comfortable during physical exertion.
Yes, warm undergarments come in various styles tailored to different activities. For example, some are designed for high-intensity sports, while others are better suited for casual wear or layering under heavier clothing. It's important to choose a style that matches your specific needs, whether for skiing, hiking, or everyday use.
Key features to look for in warm undergarments include moisture-wicking capabilities, breathability, and thermal insulation. Additionally, consider options with flat seams to reduce chafing and those that offer stretch for better mobility. These features enhance comfort and performance, especially in cold conditions.
Warm undergarments serve as the base layer in a layering system, providing insulation and moisture management against the skin. They should fit snugly to trap heat without restricting movement. Layering with mid and outer layers on top will enhance warmth and protection from the elements.
Warm undergarments are versatile and can be used in both cold and mild weather, depending on the thickness and material. In colder conditions, they provide essential insulation, while lighter options can be suitable for milder temperatures. It's important to choose the right weight and fabric based on the weather and your activity level.
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