Extend the lifespan of your broadheads with Hypodermic +P & SS 85-gr. Mechanical Broadhead Replacement Blades. This set includes three sets of blades, three sets of screws, three Extreme Shock Collars, and three Deep Six Shock Collars. The shock collars keep the blades and broadheads fitted together and produce smooth shooting. An Allen wrench is also provided for easy installment of the replacement blades. With this pack, you can replace the blades for three broadheads, either the Hypodermic +P or SS 85-gr.