ISO 4032

Covers — dimensions of metric hexagon regular (style 1) nuts, product grades A and B, including width across flats, thickness, and tolerances.

Does NOT cover (exclusions) — the following are governed elsewhere:

• Nut mechanical properties/classes → ISO 898-2.
• Bolt/screw dimensions → ISO 4014 / 4017.
• Thin, high, or flange metric nuts → their own ISO standards (e.g., ISO 4035 thin, ISO 4033 high).
• Inch-series nut dimensions → ASME B18.2.2.

ISO 4032 gives the regular metric nut size; the strength class comes from ISO 898-2.

ISO 4032 sets minimum requirements for regular metric nuts:

• Dimensions — width across flats/corners and nut thickness (style 1) by thread size.
• Product Grades — A (fine) and B (medium) tolerance classes.
• Compatibility — dimensioned to mate with ISO 4014/4017 hex bolts and screws.

ISO 4032 is the dimensional standard for metric hexagon regular (style 1) nuts — the ISO counterpart of ASME B18.2.2. It fixes across-flats size, thickness, and tolerances so the nut fits standard metric wrenches and mates with ISO 4014/4017 bolts.

It governs geometry only; the nut's strength is a property class from ISO 898-2, and thin/high/flange nut variants have their own ISO numbers. Pairing the correct property-class nut with the bolt is essential to develop full preload.

Engineering Note: Confirm both the ISO 4032 size and the ISO 898-2 property class of a metric nut — the right dimension in the wrong strength class will not carry the bolt's preload.