ISO 3506-2:2009 specifies the mechanical properties of nuts made of austenitic, martensitic and ferritic steel grades of corrosion-resistant stainless steels, when tested over an ambient temperature range of 10 °C to 35 °C. Properties vary at higher or lower temperatures.

ISO 3506-2:2009 applies to nuts:

- with nominal thread diameter d ≤ 39 mm;

- of triangular ISO metric threads with diameters and pitches in accordance with ISO 68-1, ISO 261 and ISO 262;

- of any shape;

- with width across flats as specified in ISO 272;

- with nominal heights m ≥ 0,5 d.

It does not apply to nuts requiring properties, such as locking abilities and weldability.