M8-1.25 x 55mm DIN 603 Class A2 Stainless Steel Carriage Bolt / THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 55.0 MILLIMETERS NOMINAL FASTENER LENGTH: 55.0 MILLIMETERS NOMINAL HEAD STYLE: C37 ROUND HEAD DIAMETER: 19.3 MILLIMETERS MINIMUM AND 20.6 MILLIMETERS MAXIMUM HEAD HEIGHT: 4.1 MILLIMETERS MINIMUM AND 4.8 MILLIMETERS MAXIMUM END ITEM IDENTIFICATION: 2590-01-618-5030 NECK LENGTH: 4.4 MILLIMETERS MINIMUM AND 5.6 MILLIMETERS MAXIMUM NOMINAL THREAD DIAMETER: 8.0 MILLIMETERS THREAD PITCH IN MILLIMETERS: 1.25 EXTERNAL THREAD TOLERANCE CLASS: 8G NECK WIDTH: 7.4 MILLIMETERS MINIMUM AND 8.0 MILLIMETERS MAXIMUM PART NAME ASSIGNED BY CONTROLLING AGENCY: CARRIAGE BOLT MATERIAL: STEEL OVERALL THREAD SERIES DESIGNATOR: M