This RC4WD King Off-Road Racing Shock Rebuild Kit restores worn or leaking shocks using X-ring seals, which provide an improved seal over standard O-rings. The medium kit includes X-rings, O-rings, plastic shock pistons, and e-clips sized for mid-range King shock bodies. It is a factory replacement service kit compatible with a wide range of 1/10 scale crawlers and trail trucks running King-style shocks. Keeping a kit on hand makes routine shock maintenance fast and straightforward. Features: X-ring seals for improved leak resistance over standard O-rings Includes X-rings, O-rings, shock pistons, and e-clips Medium sizing for mid-range King Off-Road Racing shock bodies Compatible with a wide range of 1/10 scale RC crawlers and trail trucks 7/7/26 cs