NOT MEASURING THE HEX END THIS IS 10MM DIA. X 5 1/8" LONG 57J$7.29 *SELF_LOCKING 10MM SWING_ARM_NUT 50'S_70'S_90'S_110'S 1/16M (207P) 207P$2.14 *10mm_NUT_PLAIN 1.25_PITCH MANY_USES REAR_SWING_ARM BOLT CT70K0_&_HK0 1/16M (65R)OEM HONDA 10MM NUT 1.25 PITCH THIS WAS STOCK ON SWING ARM BOLTS OF: CT70K0_&_HK0 65R$0.83 10MM LOCK WASHER KL 1/14K (10LOCK) 10LOCK$0.19 *OEM_HONDA_WASHER 10MM 1/16A (B63H)OEM HONDA WASHER REAR SWING ARM/TOP & BOTTOM REAR SHOCK - 10MM FLAT WASHER (63H) B63H$0.68