Complete replacement top-end kit for the Zenoah G260PUM engine. Also works as a big bore upgrade kit for the Zenoah G231PUM Engine. Includes new-style optimized stock 34mm cylinder for Zenoah G260PUM engine (found on newest 'red cap' engines), piston, piston ring, snap rings, pin washer set, cylinder base gasket, and o-rings. Note: Does not fit the old discontinued Zenoah 230PUM, as it has a different crankcase than the current 231/260PUMs that Zenoah manufactures.