Notes: 21424 HEX SOCKET HEAD CAP SCREW UNI 5931 M12X4 is original CARRARO product. 21424 HEX SOCKET HEAD CAP SCREW UNI 5931 M12X42 is commonly used in transmissions/axles/engines 427110, 427110, . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849