For grooved pins, taper and center-groove types, ISO 8744 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 8744 — Scope
ISO 8744 is "Grooved pins — Full-length taper grooved".
Tolerance & Product Grades
ISO 8744 does not divide grooved pins, taper and center-groove types 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 8744
| Nominal diameter d (mm) | Type | d_1 (mm) | a (mm) | d1 (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|
| 1.5 mm | Half-length reverse taper grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length reverse taper grooved pins | 2 | 0.25 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length reverse taper grooved pins | 2.5 | 0.3 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length reverse taper grooved pins | 3 | 0.4 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length reverse taper grooved pins | 4 | 0.5 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length reverse taper grooved pins | 5 | 0.63 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length reverse taper grooved pins | 6 | 0.8 | 12~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length reverse taper grooved pins | 8 | 1 | 14~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length reverse taper grooved pins | 10 | 1.2 | 18~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length reverse taper grooved pins | 12 | 1.6 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length reverse taper grooved pins | 16 | 2 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length reverse taper grooved pins | 20 | 2.5 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length reverse taper grooved pins | 25 | 3 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Third-length center grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Half-length center grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Third-length center grooved pins | 2 | 0.25 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length center grooved pins | 2 | 0.25 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Third-length center grooved pins | 2.5 | 0.3 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length center grooved pins | 2.5 | 0.3 | 12~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Third-length center grooved pins | 3 | 0.4 | 12~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length center grooved pins | 3 | 0.4 | 12~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Third-length center grooved pins | 4 | 0.5 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length center grooved pins | 4 | 0.5 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Third-length center grooved pins | 5 | 0.63 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length center grooved pins | 5 | 0.63 | 18~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Third-length center grooved pins | 6 | 0.8 | 22~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length center grooved pins | 6 | 0.8 | 22~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Third-length center grooved pins | 8 | 1 | 26~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length center grooved pins | 8 | 1 | 26~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Third-length center grooved pins | 10 | 1.2 | 32~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length center grooved pins | 10 | 1.2 | 32~160 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Third-length center grooved pins | 12 | 1.6 | 40~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length center grooved pins | 12 | 1.6 | 40~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Third-length center grooved pins | 16 | 2 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length center grooved pins | 16 | 2 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Third-length center grooved pins | 20 | 2.5 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length center grooved pins | 20 | 2.5 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Third-length center grooved pins | 25 | 3 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length center grooved pins | 25 | 3 | 45~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Full-length taper grooved pins | 1.5 | 0.2 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Full-length taper grooved pins | 2 | 0.25 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Full-length taper grooved pins | 2.5 | 0.3 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Full-length taper grooved pins | 3 | 0.4 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Full-length taper grooved pins | 4 | 0.5 | 8~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Full-length taper grooved pins | 5 | 0.63 | 8~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Full-length taper grooved pins | 6 | 0.8 | 10~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Full-length taper grooved pins | 8 | 1 | 12~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Full-length taper grooved pins | 10 | 1.2 | 14~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Full-length taper grooved pins | 12 | 1.6 | 14~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Full-length taper grooved pins | 16 | 2 | 24~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Full-length taper grooved pins | 20 | 2.5 | 26~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Full-length taper grooved pins | 25 | 3 | 26~120 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 1.5 mm | Half-length taper grooved pins | 0.2 | 1.5 | 8~20 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2 mm | Half-length taper grooved pins | 0.25 | 2 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 2.5 mm | Half-length taper grooved pins | 0.3 | 2.5 | 8~30 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 3 mm | Half-length taper grooved pins | 0.4 | 3 | 8~40 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 4 mm | Half-length taper grooved pins | 0.5 | 4 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 5 mm | Half-length taper grooved pins | 0.63 | 5 | 10~60 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 6 mm | Half-length taper grooved pins | 0.8 | 6 | 10~80 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 8 mm | Half-length taper grooved pins | 1 | 8 | 14~100 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 10 mm | Half-length taper grooved pins | 1.2 | 10 | 14~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 12 mm | Half-length taper grooved pins | 1.6 | 12 | 18~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 16 mm | Half-length taper grooved pins | 2 | 16 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 20 mm | Half-length taper grooved pins | 2.5 | 20 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 | |
| 25 mm | Half-length taper grooved pins | 3 | 25 | 26~200 | ISO 8741 / ISO 8742 / ISO 8743 / ISO 8744 / ISO 8745 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Grooved Pins, Taper and Center-Groove Types page.
Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
When to Specify ISO 8744
Choose ISO 8744 for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for grooved pins, taper and center-groove types.
Custom manufacturing · Made to drawing
Need a pin to this standard in a non-standard size?
Parts built to ISO 8744 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.

