4.standard:DIN,GB,JIS,ANSI,ISO
3.hardness:4.8,8.8,10.9,12.9
2.material:carbon steel,stainless steel,brass,
1.surface:Zinc palted,ZP,HDG,plain
allen bolt/allen head bolt ( hex socket bolt)
allen bolt/allen head bolt ( hex socket bolt)
1.DIN603,912 standard
2.size:M6-M8*20mm-400mm
3.ISO9000-2000