M12-1.75 x 55mm ISO 4762 Hex Drive Class 12.9 Black Oxide Finish Alloy Steel Socket Cap Screw / THREAD DIRECTION: RIGHT-HAND FASTENER LENGTH: 55.0 MILLIMETERS NOMINAL HEAD STYLE: C48 FLAT FILLISTER INTERNAL DRIVE STYLE: D5 HEXAGON NOMINAL THREAD DIAMETER: 12.0 MILLIMETERS WIDTH ACROSS FLATS: 10.0 MILLIMETERS NOMINAL THREAD PITCH IN MILLIMETERS: 1.75 SPECIAL FEATURES: GRADE 12.9; COARSE THREADS COLOR: BLACK OVERALL MATERIAL: STEEL OVERALL SURFACE TREATMENT: OXIDE OVERALL THREAD SERIES DESIGNATOR: ISO M