The Toms Tactical AR-15 H1 Carbine Buffer is 100% made in the USA. This buffer is machined from billet aluminum and weighs 3.6 - 3.8 oz. The heavier weight buffer is used to slow down the cycle rate on carbine style AR rifles which helps lengthen receiver life. A heavyweight buffer could potentially increase performance on hotter loads by slowing the cycle rate enough to allow the magazine to ready a new round for the chamber.