This page covers M2.5 Socket Head Cap Screws to ISO 4762 / DIN 912: the full dimensional row, hole and tool sizes, proof-load data and typical applications. All values are taken from the governing standards (ISO 4762 / DIN 912 together with ISO 273, ISO 724 and ISO 898-1 where applicable).
M2.5 Dimensional Row (ISO 4762 / DIN 912)
| Size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Hex key s (mm) | Socket depth t min (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M2.5 | 0.45 | 4.5 | 2.5 | 2.0 | 1.1 | ISO 4762 / DIN 912 |
Spanner & Drive for M2.5 Socket Head Cap Screws
The hex socket for M2.5 Socket Head Cap Screws is shown in the spec table — use the matching Allen / hex key (an ISO 2936 hex key set covers the full range). A T-handle Allen key gives the best feel for setting preload by feel; for production work use a torque-controlled driver.
Common Applications for M2.5 Socket Head Cap Screws
M2.5 Socket Head Cap Screws are commonly specified for electronics, PCB hardware, optical mounts and small-scale machinery.
Installation Tips for M2.5 Socket Head Cap Screws
- Use a quality Allen key fully seated in the socket — partial engagement is the most common cause of stripped sockets at this size.
- For countersunk and button-head variants, chamfer the through-hole to seat the head flush without preloading the head/shank fillet.
- At M2.5 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 M2.5
For M2.5, pair with a M2.5 hex nut (ISO 4032 / DIN 934) and, where used, a M2.5 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
