Notes: 171301-77720 COUPLER is original YANMAR product. 171301-77720 COUPLER5 is commonly used in transmissions/axles/engines 2TNE68-ETB, 2TNE68-ETBA, 3TNE68-ADCL, 3TNE68-ENSR, 3TNE68-NSR, . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849