# 126 — Fastener standard equivalences: DIN to ISO / EN crossover

For 126, fastener description is Product grade C washers, designed for use with hexagon head bolts and nuts; iso equivalent is 7091; interchangeability is Nominal sizes changed; modification notes is Nominal sizes changed, verified against its source on 2026-08-12.

- **DIN standard:** 126 _(verified: appears in the quote below)_
- **Fastener description:** Product grade C washers, designed for use with hexagon head bolts and nuts _(verified: appears in the quote below)_
- **ISO equivalent:** 7091 _(verified: appears in the quote below)_
- **Interchangeability:** Nominal sizes changed _(verified: appears in the quote below)_
- **Modification notes:** Nominal sizes changed _(verified: appears in the quote below)_

## What the source says

> Product grade C washers, designed for use with hexagon head bolts and nuts | 126 | 7091 | | | 7091 | 2000-11 | Plain washers – Normal series, Product grade C | Nominal sizes changed |

## 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 **Product grade C washers, designed for use with hexagon head bolts and nuts**, as of 2026-08-12.

> Product grade C washers, designed for use with hexagon head bolts and nuts | 126 | 7091 | | | 7091 | 2000-11 | Plain washers – Normal series, Product grade C | Nominal sizes changed |

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

trfastenings.com says fastener description is **Product grade C washers - designed for use with Hexagon Head Bolts and Nut**, as of 2026-08-12.

> DIN 126 | ISO 7091 | | Product grade C washers - designed for use with Hexagon Head Bolts and Nut |

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/).