Historical
ISO 7041:2002
Prevailing torque type hexagon nuts (with non-metallic insert), style 2 - Property classes 9 and 12
ISO 7041:2002 specifies the characteristics of prevailing torque type hexagon nuts (with non-metallic insert), style 2, with threads from M5 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 9 and 12.
International Organization for Standardization [iso]