Notes: 24311-000210 O-RING, 1AP21.0 is original YANMAR product. 24311-000210 O-RING, 1AP21.05 is commonly used in transmissions/axles/engines 2TNE68-BL2, 2TNE68C-KG2, 3TNE68-AC, 3TNE68-ADCL, 3TNE68C-KG2, . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849