For General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087), the M4 thread sits in the small-to-medium range of the catalog and is one of the most-asked general flat washer — gb/t 97.1 / iso 7089 (series 087) in this family. The dimensional and assembly data follow.
M4 Dimensional Row (GB/T 97.1 / ISO 7089)
| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness t (mm) | Reference standard |
|---|---|---|---|---|
| M4 | 4.3 | 9.0 | 0.8 | ISO 7089 / GB/T 97.1 |
Spanner & Drive for M4 General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087)
Drive geometry for M4 General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087) is given by the row above; match the tool to the listed values.
Common Applications for M4 General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087)
M4 General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087) are commonly specified for small electronics hardware and precision assemblies.
Installation Tips for M4 General Flat Washer — GB/T 97.1 / ISO 7089 (Series 087)
- At M4 the joint is sensitive to over-torque — use a torque-limiting driver and check the head doesn't bury into a softer counterpart.
Mating Parts for M4
A M4 flat washer pairs with a M4 bolt/screw and matching M4 nut.
When to Step Up or Down from M4
When the joint preload approaches the proof load of M4 class 8.8, step up to M5 class 8.8 (or move to M4 class 10.9). When the joint is over-specified, M3 often saves weight and cost without losing the safety margin.