This page covers M16 Flat Washers to ISO 7089 / ISO 7093: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (ISO 7089 / ISO 7093 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M16 Dimensional Row (ISO 7089 / ISO 7093)
| For bolt size | Inner diameter d1 min (mm) | Outer diameter d2 max (mm) | Thickness h (mm) | Reference standard |
|---|---|---|---|---|
| M16 | 17.0 | 30.0 | 3.0 | ISO 7089 |
Spanner & Drive for M16 Flat Washers
Drive geometry for M16 Flat Washers is given by the row above; match the tool to the listed values.
Common Applications for M16 Flat Washers
M16 Flat Washers are commonly specified for medium-duty structural joints.
Mating Parts for M16
A M16 flat washer pairs with a M16 bolt/screw and matching M16 nut.
When to Step Up or Down from M16
When the joint preload approaches the proof load of M16 class 8.8, step up to M20 class 8.8 (or move to M16 class 10.9). When the joint is over-specified, M12 often saves weight and cost without losing the safety margin.

