Standard: DIN 915. Thread length:3mm 4mm 5mm 6mm 8mm 12mm 16mm 20mm 25mm 30mm 35mm 40mm 45mm 50mm. 12.9 grade bolts usually refer to ultra-high strength screws made of SCM435 alloy steel, with a minimum tensile strength of 1220 MPa and a hardness of 39-44 HRC.
