The KORE 3-Blade Shock Collar by Rage prevents the blade on any of your Rage 3-Blade KORE broadheads from prematurely deploying. If you happen to bump your arrow or broadhead while on a stand or stalking, this shock collar keeps the blade secure and steady. Shock collars are designed to break upon impact so you will need to be replaced after each shot. Inspect for any damage prior to use to ensure proper function. Comes as a single shock collar.