The Sound Deadening System is engineered to eliminate noise and shock throughout the string, limbs, and stirrup for deadly suppressed performance. This four-component package works in sync to dramatically reduce vibration and noise when the crossbow is fired, resulting in a much smoother shooting experience and effectively increases your success in chasing game. Works on all Excalibur hunting model crossbows. PRODUCT# 95913 Package Includes: Over-Moulded Rubberized Stirrup Ex-Shox String Stars R.A.V.S. Silencers NOTE: Excalibur&';s Crossbow Stringing Aid #2096 is required for installation of the Sound Deadening System