Metric hex nut sizes and dimensions are shown in the following chart according to ISO 4032, ISO 4033, ISO 4034 and ISO 4759-1 standards.
Some important notes from the ISO standards about metric hex nuts:
- ISO 4032 specifies the characteristics of hex regular nuts, style 1, with threads from M1.6 up to
including M64, with product grade A for threads d ≤ M16 and product grade B for threads d > M16.
- Mechanical properties of ISO 4032 hex regular nuts: Steel - M3 ≤ d ≤ M39 - Property class 6, 8, 10 , Stainless steel - d ≤ M24: Property class A2-70, A4-70 , M24 < d ≤ M39
- Property class A2-50, A4-50
- ISO 4033 specifies the characteristics of hex high nuts, style 2, with threads from M5 up to and
including M36, with product grade A for threads d ≤ M16 and product grade B for threads d > M16.
- Mechanical properties of ISO 4033 hex high nuts: Steel - Property class 9 and 12
- ISO 4034 specifies the characteristics of hex regular nuts, with threads from M5 up to and including M64
and product grade C.
- Mechanical properties of ISO 4034 hex regular nuts: Steel - M16 ≤ d - Property class 5, M16 < d ≤ M39 - Property class 4, 5
Note 1: Dimensions are in mm.
Note 2 :Requirements for electroplating are covered in ISO 4042 for steel nuts
Note 3: Requirements for nonelectrolytically applied zinc flake coatings are covered in ISO 10683
for steel nuts.
Note 4: Non-preferred threads according to ISO standards: M3.5, M14, M18, M22, M27, M33, M39, M45, M52, M60.
Product Grade A, Grade B and Grade C: The product grades refer to the size of the tolerances where grade A is the most precise and grade C is the least
precise as defined in the ISO 4759-1:2000 standard.