DIN 6900-5-1990
Hexagon head bolts and conical spring washers assemblies
Q 141-1999
Hexagon head bolts and conical spring washers assemblies
Q 141-1999
Hexagon head bolts and large conical spring washers
QC/T 600-1999
Hexagon head bolts and conical spring washers assemblies
QC/T 600-1999
Hexagon head bolts and large conical spring washers
DIN 6900-5-2004
Hexagon head bolts and conical spring washers assemblies
Q 141-2012
Hexagon head bolts and large conical spring washers assemblies