Notes: 123900-22900 PISTON ASSY, 0.25 OS is original YANMAR product. 123900-22900 PISTON ASSY, 0.25 OS5 is commonly used in transmissions/axles/engines 4TNE106-AMM, 4TNE106-TB, 4TNE106T-G1A, 4TNE106T-SA, 4TNE106-G1A, . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849