Gabriel G51100 Ultra Spring Seat Orifice Disk with variable nine-stage valving provides consistent oil flow G-Force technology for quicker response, improved product life, and consistent, reliable ride and control Stable Steer valving provides response from all four corners for a stable, safe ride G-Force piston is bonded iron construction for durability and longer life, along with the heavy duty compression head valve that withstands extreme impact Leak-proof piston seal and rod guide eliminates oil bypass