# 931-1 — Fastener standard equivalences: DIN to ISO / EN crossover

For 931-1, fastener description is Hexagon head bolts with shank; M 1,6 to M 39 screw threads, Product grades A and B; iso equivalent is 4014; interchangeability is Nominal size extended; width across flats according to DIN ISO 272 included; modification notes is Nominal size extended; width across flats according to DIN ISO 272 included, verified against its source on 2026-08-12.

- **DIN standard:** 931-1 _(verified: appears in the quote below)_
- **Fastener description:** Hexagon head bolts with shank; M 1,6 to M 39 screw threads, Product grades A and B _(verified: appears in the quote below)_
- **ISO equivalent:** 4014 _(verified: appears in the quote below)_
- **Interchangeability:** Nominal size extended; width across flats according to DIN ISO 272 included _(verified: appears in the quote below)_
- **Modification notes:** Nominal size extended; width across flats according to DIN ISO 272 included _(verified: appears in the quote below)_

## What the source says

> Hexagon head bolts with shank; M 1,6 to M 39 screw threads, Product grades A and B | 931-1 | 4014 | 24014 | 4014 | 4014 | 2001-03 | Hexagon head bolts – Product grades A and B | Nominal size extended; width across flats according to DIN ISO 272 included |

## 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.

### Fastener description

fullerfasteners.com says fastener description is **Hexagon head bolts with shank; M 1,6 to M 39 screw threads, Product grades A and B**, as of 2026-08-12.

> Hexagon head bolts with shank; M 1,6 to M 39 screw threads, Product grades A and B | 931-1 | 4014 | 24014 | 4014 | 4014 | 2001-03 | Hexagon head bolts – Product grades A and B | Nominal size extended; width across flats according to DIN ISO 272 included |

Source: https://fullerfasteners.com/tech/din-iso-en-crossover-chart/

trfastenings.com says fastener description is **M1,6 to M39 Hexagon Cap Screws partially threaded - product grades A and B**, as of 2026-08-12.

> DIN 931-1 | ISO 4014 | BS3692 | M1,6 to M39 Hexagon Cap Screws partially threaded - product grades A and B |

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


## Source

- https://fullerfasteners.com/tech/din-iso-en-crossover-chart/
- https://www.trfastenings.com/knowledge-base/engineering-data/fastener-standards

Last verified: 2026-08-12. Review by: 2028-08-11.
Part of [Fastener standard equivalences: DIN to ISO / EN crossover](https://referencesource.org/fastener-thread-standard-equivalence/).