1998DS/EN 1664:1998 Prevailing torque type all-metal hexagon nuts with flange
1985DS/ISO 7044:1985 Prevailing torque type all-metal hexagon nuts with flange
DS/ISO 7044:1985 Prevailing torque type all-metal hexagon nuts with flange was changed to DS/EN 1664:1998 Prevailing torque type all-metal hexagon nuts with flange.