ISO 10664 is the standard cited for torx and torx-plus screwdriver bits. This page sets out what the standard controls for this part, reproduces the dimensional table supplied against it, and notes the related designations referenced on drawings.
ISO 10664 — Scope
The table below lists the dimensions catalogued for torx and torx-plus screwdriver bits under ISO 10664. The scope of ISO 10664 itself is not summarised here — where a figure matters, confirm it against the published document.
Tolerance & Product Grades
Product grade is a concept from dimensional fastener standards and does not apply to ISO 10664. Tolerances for this part are the limits shown against each dimension in the table.
Dimensions Specified by ISO 10664
| Bit | Drive | Typical mating screw | Service |
|---|---|---|---|
| T10 | Torx | M3 hexalobular | electronics, appliance |
| T15 | Torx | M3.5 hexalobular | appliance, light assembly |
| T20 | Torx | M4 hexalobular | general assembly |
| T25 | Torx | M5 hexalobular | decking, general assembly |
| T27 | Torx | M5 – M6 hexalobular | construction screws |
| T30 | Torx | M6 hexalobular | structural timber screws |
| T40 | Torx | M8 hexalobular | heavy assembly |
| T20 IP | Torx security (pin-in) | M4 tamper-resistant | public and outdoor equipment |
| T25 IP | Torx security (pin-in) | M5 tamper-resistant | public and outdoor equipment |
Companion Standards
A complete specification for torx and torx-plus screwdriver bits normally cites several documents: one for the geometry, one for the material or mechanical properties, and one for the finish. ISO 10664 is one of them, not all of them.
When to Specify ISO 10664
Choose ISO 10664 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for torx and torx-plus screwdriver bits.
Custom manufacturing · Made to drawing
Need a fastener tool to this standard in a non-standard size?
Parts built to ISO 10664 are already in the catalog, so a special is usually a variation on existing tooling rather than a new design — which is what keeps the cost down.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
