Width across flats
| Symbol | s |
|---|---|
| Unit | mm |
| Attribute-ID | vdi_2230_width_across_flats |
| Numeric ID | 12247 |
| Value Type | PMTechValue |
The width across flats s specifies the distance between two parallel surfaces on the bolt head, which are used for torque transmission by means of positive locking. This size is used on tools such as open-end and hex keys, but also on the associated bolt or nut.