Sims Vibration Laboratory has revolutionized the crossbow industry with the introduction of the first of its kind, crossbow silencing system. Designed to install on virtually any crossbow, this new three-part dampening system is guaranteed to reduce sound and vibration to a level never experienced before. The Limbsaver Crossbow Silencer System consists of the Limbsaver Ultra, a pair of crossbow String Leeches and a Bolt Retainer Dampener.