This is the best AR-15 9 mm buffer or you can buy. Made of heat treated stainless steel this 8 ounce 9 mm buffer makes shooting your 9 mm pistol upper a joy. Replaces your standard 3 oz. buffer and uses your existing spring. Reduces require felt substantially. Buy with confidence at Veriforce Tactical, where we ship same or next business day and guarantee our products 100%.