Zenoah 32mm piston. New-style optimised piston as featured on 'red cap' engines for use with the .8mm piston ring.  PMW part # 4320 Zenoah part # T2071-41110 FG part # 07308/09 Stock Part on the  G230RC  G240RC   G231PUH  G231PUM Use Zenoah pistons with Zenoah top ends, CY top ends should use CY pistons