These heavy-duty, lightweight fire hose couplings are made from 6061-T6 high-strength aluminum alloy. Swivels are attached with a piston ring, stainless balls, or roller bearings. No roll-over or still threads are ever used to attach swivels. The 6061-T6 aircraft aluminum alloy gets a smooth hardcoat finish. Weight is one third that of cast brass, and three times as strong. Comes complete with rings and gaskets. All gaskets are lathe cut and the expansion rings provided are 85-15 red brass.