WOSSNER PISTON KIT TRX XR400EX 85 44 8604D050In house designed and manufactured; all forgings are produced in Wssners company owned forging operation, 4 stroke pistons are made using a double bridged forging design, Lightweight pistons with the tightest piston wall clearances in the industry give you a quieter running engine, Standard and oversize pistons for most models, with high compression ratios available for 4 stroke applications, All piston skirts are supplied with a Moly coating to