Notes: 129978-22690 PISTON ASSY, 0.25 OS is original YANMAR product. 129978-22690 PISTON ASSY, 0.25 OS2 is commonly used in transmissions/axles/engines 4TNV94HT-ZSKTC, 4TNV94HT-ZSKTC, . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849