# DIN 931 · M22 · Widths across flats in mm — Sizes where a DIN fastener and its ISO equivalent are not interchangeable

For DIN 931, size is M22; dimension that differs is Widths across flats in mm; iso standard is ISO 4014; din value is 32; iso value is 34, verified against its source on 2026-10-12.

- **DIN standard:** DIN 931 _(verified: appears in the quote below)_
- **ISO standard:** ISO 4014 _(verified: appears in the quote below)_
- **Size:** M22 _(verified: appears in the quote below)_
- **Dimension that differs:** Widths across flats in mm _(verified: appears in the quote below)_
- **DIN value:** 32 _(verified: appears in the quote below)_
- **ISO value:** 34 _(verified: appears in the quote below)_

## What the source says

**ISO standard, DIN value and ISO value:** The source prints these values inside the passage below but does not name them there. The passage shows where each one appears; what ties them to this record is the position on the page, not anything the passage says.

> Widths across flats in mm for hexagon head bolts for hexagon head bolts (normal series according to ISO 272) DIN 558 ISO 4018 DIN 601 ISO 4016 DIN 931 ISO 4014 Nominal Ø DIN 6921 EN 1665 DIN 933 ISO 4017 DIN 960 ISO 8765 DIN 961 ISO 8676 M1.6 3.2 3.2 – – M2 4 4 – – M2.5 5 5 – – M3 5.5 5.5 – – M4 7 7 – – M5 8 8 8 8 M6 10 10 10 10 M8 13 13 13 13 M10 17 16 15 16 M12 19 18 16 18 M14 22 21 18 21 M16 24 24 21 24 M18 27 27 – – M20 30 30 20 30 M22 32 34 – –

## Source

- https://www.wurthindustry.ca/media/downloads/wic_pdfs/Fasteners_DIN-EN-ISO_Standards.pdf

Last verified: 2026-10-12. Review by: 2029-10-11.
Part of [Sizes where a DIN fastener and its ISO equivalent are not interchangeable](https://referencesource.org/fastener-standard-interchangeability-exceptions/).