O.S. Engines 25203200 .50 SX-H Piston FEATURES: Constructed of aluminum; Replaces worn or damaged pistons INCLUDES: One Piston for the O.S. Max .50SX and the .50SX-H Helicopter Engines REQUIRES: Removing Cylinder (OSMG5279), installing Piston Ring (OSMG7790) and using Piston Pin (OSMG7691) and Pin Retainer (OSMG7482) to attach to Con