according to ISO 898, part 2

1) Nuts style 1 (ISO 4032) ≈ 0,9 d nuts
2) Nuts style 2 (ISO 4033) ≈ 1,0 d nuts
3) Class 8 ≤ M16 only type 1 (not heat-treated) 
    > M16 type 1 (hardened and tempered) and type 2 (not heat-treated)
according to ISO 898, part 2

1) Nuts style 1 (ISO 4032) ≈ 0,9 d nuts
2) Nuts style 2 (ISO 4033) ≈ 1,0 d nuts
3) Class 8 ≤ M16 only type 1 (not heat-treated) 
    > M16 type 1 (hardened and tempered) and type 2 (not heat-treated)
The mechanical properties as listed apply to heat-treated nuts:

| Notes
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