This is a must have accessory if you have an AR-10, LR-308 are any of the larger caliber AR-15's where recoil is an issue. Also adds great comfort when shooting in Tee-shirts. LimbSaver slip-on recoil pads feature a patented three-step recoil reduction technology that reduces up to 70% of felt recoil, and maintains target acquisition. They feature a 12-month warranty by Limbsaver. Slips right on to your stock with no tools or effort.