For internally threaded dowel pin, ISO 8735 is the governing document for the dimensions listed below. Mechanical and performance requirements for this part family are set by its own standards, not by the bolt and screw property-class documents.
ISO 8735 — Scope
ISO 8735 is "Parallel pins with internal thread, hardened".
Tolerance & Product Grades
ISO 8735 does not divide internally threaded dowel pin — gb/t 118 / iso 8735 (series 099) into product grades. Tolerances are given as limits on the individual dimensions in the table.
Where a general-tolerance class is cited on the drawing instead, it applies to the dimensions not otherwise toleranced.
Dimensions Specified by ISO 8735
| Nominal diameter d (mm) | Length L (mm) | Internal thread | Material | Reference standard |
|---|---|---|---|---|
| 4 | 16 | M3 | Alloy steel | ISO 8735 / GB/T 118 |
| 5 | 20 | M4 | Alloy steel | ISO 8735 / GB/T 118 |
| 6 | 24 | M4 | Alloy steel | ISO 8735 / GB/T 118 |
| 8 | 30 | M5 | Alloy steel | ISO 8735 / GB/T 118 |
| 10 | 40 | M6 | Alloy steel | ISO 8735 / GB/T 118 |
| 12 | 50 | M8 | Alloy steel | ISO 8735 / GB/T 118 |
| 16 | 60 | M10 | Alloy steel | ISO 8735 / GB/T 118 |
| 20 | 80 | M12 | Alloy steel | ISO 8735 / GB/T 118 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Internally Threaded Dowel Pin — GB/T 118 / ISO 8735 (Series 099) page.
Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify ISO 8735
Choose ISO 8735 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for internally threaded dowel pin — gb/t 118 / iso 8735 (series 099).
Custom manufacturing · Made to drawing
Need a pin to this standard in a non-standard size?
Parts built to ISO 8735 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. Made by cold heading or turning.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

