Top End Piston Kit - Banshee YZ350 - 65.95 mm The piston is heat treated with a T-5 hardening and tempering cycle, The piston skirt is coated with high-tech Molybdenum Disulphite for faster break in time and increased piston life, The cast piston is gravity-cast aluminum alloy (not forged) with 18% silicone content, Cast OE piston, Top end kit includes piston, rings, pins, circlips, top-end gaskets, and wrist pin bearing