... steel (4).Length:6-300mm,3/4"-5'' Hex bolt Material: Iron, stainless steel SUS 316, SUS304, SUS201 ... and SUS200, copper and etc.Hex bolt Material: Iron, stainless steel SUS 316, SUS304, SUS201 ... and SUS200, copper and etc. Bolt Standard: DIN 933, DIN 931, DIN 558, JIS ISO ... as Zinc plate, plain finish, copper plate, nickel plate Grade: 4.8, 6.8, 8.8, 10.9, 12 ...