Notes: 209-4309 P.O. 24667 SHIM 63X40.3X3.2 is original CATERPILLAR product. 209-4309 P.O. 24667 SHIM 63X40.3X3.21 is commonly used in transmissions/axles/engines . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849