The Rage® Extreme Shock Collars help your broadheads function properly in the field. The shock collars fit on Rage® Extreme and Hypodermic Standard broadheads to ensure the blades do not deploy early in case you bump your arrow while hunting in a treestand. They also break upon contact and need replaced after you take a shot. The Rage® Shock Collars keep your blades in working order for that next kill.