Gabriel G51721 Ultra Spring Seat Precison Engineered for today's passenger cars with G-Force technology for the ultimate in safety and performance, Gabriel Ultra is designed to provide improved comfort and control, long life and durability, and maximum shock performance. Infinitely Variable Damping for on-demand control on all road conditions; StableSteer valving improves tire contact with the road for control, safety and performance, and the G-Force piston provides sintered iron construction for long life and durability Orifice Control Disc for consistent control comfort and stability and an OE-design single lip oil seal that minimizes friction for optimal comfort and performance Super-finished chromed piston rod provides superior corrosion resistance, enhances sealing properties, ensures proper seal lubrication and provides a more consistent wear surface Leak-proof piston seal which extends product life