The Strike Industries GLock Shock Buffer is a polyester based thermoplastic polyurethane barrier that is uniquely designed to absorb recoil. The GSB was designed to increase durability between the areas of the metal slide and polymer frame while also decrease the amount of overall wear. It is compatible with several models of Glock and comes in 115 degree of hardness for the user’s desire comfort level of recoil relief. The relief gained will also decrease the shock to your hands which prevents muscle fatigue and allows for more control for the next shot. It is engineered with a retaining design to ensure buffer will be secured on the slide and has added extra cushion knobs for extra buffer. *Note- This model will not fit Gen4 Glock.