M12-M33 ,10 Class, Hardness: HRC26-36, fully hardened and tempered to ... .9 Class, minimum tensile strength 170,000 psi.Nuts:M12-M33 ,10 Class, Hardness: HRC26-36, fully hardened and tempered to ... ( { 'aImgSrc': aBigImageSrc } ); } )(); Manufacture wheel Nuts/hex nuts/flange nuts (M12-M33)