Metric Size
M2.5
M2.5 coarse thread — 0.45 mm pitch, 2.05 mm tap drill, 2.9 mm normal clearance hole, 2 mm hex key.
Last verified: 2026-07-10
| Pitch(mm)Coarse-thread pitch (ISO 261). | 0.45 |
|---|---|
| Tap drill(mm)For ~75% thread — major Ø minus pitch. | 2.05 |
| Clearance (normal)(mm)Normal clearance hole (ISO 273). | 2.9 |
| Hex key(mm)Socket cap-screw hex key (ISO 4762). | 2 |
| Typical use | Electronics, small mechanisms |
Other metric fastener reference
Sources
- ISO 261 — ISO general-purpose metric screw threads (coarse pitch)
- ISO 273 — clearance holes for bolts and screws (normal fit)
- ISO 4762 — hexagon socket head cap screws (hex key sizes)