This 10/22 accessory is a must have! An inexpensive quick to install upgrade. A great addition if you want less battering, vibration, and recoil noise. Not recommended for use with magnum receivers. FEATURES: Aftermarket replacement for the 10/22 bolt stop Steel core with padded tubing cover Eliminate "bolt battering" of the receiver Dampen cycling vibration Installation Instructions: First install the tubing beginning from the inside center of the receiver and pushing it out through the right and left side. (If you attempt to thread the tubing from the outside left or right it's more difficult) Second from th Mfg: Kidd Innovative Design