The Piston Kit is part of the latest collection from Wossner. . Features: . In-house designed and manufactured; all forgings are produced in Wossner?s 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 reduce friction and assist in break in . All piston kits include piston, ring, wrist pin and pin locks . Wossner piston kits are used by leading Supercross, Arenacross and MX GP teams . Specifications: . Bore - Oversize: Standard . Compression Ratio: 14.1 . Engine Type: 4-Stroke . Piston Diameter: 77.98 mm . Piston Material: Aluminum Alloy| Forged| Steel . Piston Size: Standard Size C . Product Name: Piston Kit . Ring Material: Cast| Steel . Skirt Coating: Moly Coated . Stroke Length: 52.20 mm . Style: Performance Replacement . Type: Replacement Forged Piston . To fit: . KAWASAKI KX 250 X 2021 Cross Country All Models . KAWASAKI KX 250 X 2022 Cross Country All Models . KAWASAKI KX 250 2021 All Models . KAWASAKI KX 250 2022 All Models . Manufacturer part number: 8989DC . View all Wossner Parts. View all Parts and spares. .