2b thread class right-hand 16 thread quantity per inch 18-8 stainless steel toplock hex locknut locking feature is distorted threads that create a vibration-resistant friction-fit so the nut stays put; nut is not reusable; mcmaster-carr cage 2V507 purchases this item from oem yellow woods & roads less traveled co. 655 union blvd, totawa, nj 07512-2402 phone (973) 890-9101; part number for oem is 31-top-37c; oem does not have a cage code
