Notes: 2074262 HEX HEAD SCREW UNI 5739 M16X75 - - REG.S is original CATERPILLAR product. 2074262 HEX HEAD SCREW UNI 5739 M16X75 - - REG.S1 is commonly used in transmissions/axles/engines . if you have any questions please do not hesitate to contact us via Whatsapp +17275652849