Monroe 901015 Max-Lift Hatch Lift Support Nitro-Carburized Rod for exceptional corrosion resistance and durability Durable Plastic Rod Guide reduces potential rod abrasion Main Seal provides positive closure for high-pressure gas Stop Collar and Limiting Groove assure precise extended length High-Strength Piston Assembly with Leak-Proof Seal helps prevent fluid leakage around the piston, allowing the fluid to pass efficiently through the piston valving components, providing controlled lift and consistent performance