Notes: 1987822 - p/o 20063 SEAL RING 48X65X16.5 SF6 is original CATERPILLAR product. 1987822 - p/o 20063 SEAL RING 48X65X16.5 SF61 is commonly used in transmissions/axles/engines . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849