# DIN 6923 — DIN / ISO / BS fastener equivalents and the sizes where they are not interchangeable

For DIN 6923, iso standard is DIN EN 1661; part is Hex Nut with Flange; interchangeability verdict is Check spec, verified against its source on 2026-08-05.

- **DIN standard:** DIN 6923 _(verified: appears in the quote below)_
- **ISO standard:** DIN EN 1661 _(verified: appears in the quote below)_
- **Part:** Hex Nut with Flange _(verified: appears in the quote below)_
- **Interchangeability verdict:** Check spec _(verified: appears in the quote below)_

## What the source says

> Hex Nut with Flange | DIN 6923 | DIN EN 1661 | Check spec | Flange geometry/tolerance.

## Sources disagree

More than one authority states this, and they do not state the same
thing. Both are reproduced with the source each came from.

### ISO standard

monsterbolts.com says iso standard is **DIN EN 1661**, as of 2026-08-05.

> Hex Nut with Flange | DIN 6923 | DIN EN 1661 | Check spec | Flange geometry/tolerance.

Source: https://monsterbolts.com/pages/common-din-numbers-for-metric-fasteners

trfastenings.com says iso standard is **ISO 1661**, as of 2026-08-05.

> DIN 6923 | ISO 1661 | | Hexagon Nuts with flange |

Source: https://www.trfastenings.com/knowledge-base/engineering-data/fastener-standards


### Part

monsterbolts.com says part is **Hex Nut with Flange**, as of 2026-08-05.

> Hex Nut with Flange | DIN 6923 | DIN EN 1661 | Check spec | Flange geometry/tolerance.

Source: https://monsterbolts.com/pages/common-din-numbers-for-metric-fasteners

trfastenings.com says part is **Hexagon Nuts with flange**, as of 2026-08-05.

> DIN 6923 | ISO 1661 | | Hexagon Nuts with flange |

Source: https://www.trfastenings.com/knowledge-base/engineering-data/fastener-standards


## Source

- https://monsterbolts.com/pages/common-din-numbers-for-metric-fasteners
- https://www.trfastenings.com/knowledge-base/engineering-data/fastener-standards

Last verified: 2026-08-05. Review by: 2029-08-04.
Part of [DIN / ISO / BS fastener equivalents and the sizes where they are not interchangeable](https://referencesource.org/fastener-standard-interchangeability-exceptions/).