Notes: 3318538 CASSETTE RAD.SHAFT SEAL 150X180X/ 14.5/1 is original CATERPILLAR product. 3318538 CASSETTE RAD.SHAFT SEAL 150X180X/ 14.5/11 is commonly used in transmissions/axles/engines . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849