Specification summary of ISO 8741 as applied to grooved pins, taper and center-groove types: the dimensions the standard fixes, the full size range supplied, and the related designations commonly cross-referenced.
ISO 8741 — Scope
ISO 8741 is "Grooved pins — Half-length reverse-taper grooved".
Tolerance & Product Grades
ISO 8741 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 8741
| 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.
Companion Standards
ISO 8741 controls the geometry of grooved pins, taper and center-groove types. Surface finish is governed by separate finish standards such as ISO 4042 for electroplating, and corrosion testing by ISO 9227 (neutral salt spray). Mechanical performance is set by the documents specific to this part family — ISO 898-1 and ISO 898-2 apply to bolts, screws, studs and nuts, and not here.
Custom manufacturing · Made to drawing
Need a pin to this standard in a non-standard size?
Parts built to ISO 8741 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.

