ISO 8673 Hex Regular Nuts (Fine Pitch)
ISO 8673 hexagon regular nuts with metric fine pitch thread, M8×1 to M64×4 — the standard-height hex nut in the fine-pitch series, with the collected per-size tables: pitch options, c, d a, d w, e, m, m w and s.
Last updated: 2026-11
Specifications
ISO 8673 is the regular (standard-height) hex nut of the metric fine-pitch series — the nut that pairs with ISO 8765 fine-pitch bolts and ISO 8676 fine-pitch screws, and the replacement designation for the DIN 982-era coarse assumptions when a joint needs a finer thread. Why fine pitch: a finer helix angles the thread flanks so the same clamp comes from lower torque, the nut backs off less under vibration because each turn moves it less, and adjustment on a threaded rod is finer. The collected tables run M8×1 through M64×4 (parenthesized sizes are the non-preferred series as printed), tabulating per size the pitch options — the source prints a Fine thread-1 / Fine thread-2 pair per size where two fine pitches exist, and on the Fine thread-2 row it merges the minus sign into the value ("-1.25", "-1.5"), kept verbatim and disclosed so confirm the intended pitch at RFQ — plus chamfer c, washer-face d a, bearing-face d w, across-corners e, height m (max/min), the m w bearing check and across-flats s. Property classes, materials and finishes are not printed by the collected specification and stay per RFQ.
| Standard | ISO 8673 — hexagon regular nuts, style 1, with metric fine pitch thread |
|---|---|
| Series | M8×1 – M64×4 (seven source column groups; parenthesized sizes are the non-preferred series as printed) |
| Tabulated geometry | Per size: pitch (Fine thread-1/2 options as printed), c (max/min), d a (max/min), d w (min), e (min), m (max/min, 6.8–51 mm), m w (min), s (max=nominal/min, 13–95 mm) |
| Function | Standard-height clamp nut for fine-pitch bolted joints — lower torque for the same clamp, finer adjustment, better vibration behaviour than the coarse series |
| Property classes / materials | Not tabulated by the collected specification — per RFQ |
| Attribute | M8 | M10 | M12 |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 1 | 1 | 1.5 |
| Fine thread-2 | - | -1.25 | -1.25 |
| c — max | 0.6 | 0.6 | 0.6 |
| min | 0.15 | 0.15 | 0.15 |
| d a — max | 8.75 | 10.8 | 13 |
| min | 8 | 10 | 12 |
| d w — min | 11.63 | 14.63 | 16.63 |
| e — min | 14.38 | 17.77 | 20.03 |
| m — max | 6.8 | 8.4 | 10.8 |
| min | 6.44 | 8.04 | 10.37 |
| m w — min | 5.15 | 6.43 | 8.3 |
| s — max=nominal size | 13 | 16 | 18 |
| min | 12.73 | 15.73 | 17.73 |
| Attribute | (M14) | M16 | (M18) |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 1.5 | 1.5 | 1.5 |
| Fine thread-2 | - | - | - |
| c — max | 0.6 | 0.8 | 0.8 |
| min | 0.15 | 0.2 | 0.2 |
| d a — max | 15.1 | 17.3 | 19.5 |
| min | 14 | 16 | 18 |
| d w — min | 19.64 | 22.49 | 24.85 |
| e — min | 23.36 | 26.75 | 29.56 |
| m — max | 12.8 | 14.8 | 15.8 |
| min | 12.1 | 14.1 | 15.1 |
| m w — min | 9.68 | 11.28 | 12.08 |
| s — max=nominal size | 21 | 24 | 27 |
| min | 20.67 | 23.67 | 26.16 |
| Attribute | M20 | (M22) | M24 |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 2 | 1.5 | 2 |
| Fine thread-2 | -1.5 | - | - |
| c — max | 0.8 | 0.8 | 0.8 |
| min | 0.2 | 0.2 | 0.2 |
| d a — max | 21.6 | 23.7 | 25.9 |
| min | 20 | 22 | 24 |
| d w — min | 27.7 | 31.35 | 33.25 |
| e — min | 32.95 | 37.29 | 39.55 |
| m — max | 18 | 19.4 | 21.5 |
| min | 16.9 | 18.1 | 20.2 |
| m w — min | 13.52 | 14.48 | 16.16 |
| s — max=nominal size | 30 | 34 | 36 |
| min | 29.16 | 33 | 35 |
| Attribute | (M27) | M30 | (M33) |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 2 | 2 | 2 |
| Fine thread-2 | - | - | - |
| c — max | 0.8 | 0.8 | 0.8 |
| min | 0.2 | 0.2 | 0.2 |
| d a — max | 29.1 | 32.4 | 35.6 |
| min | 27 | 30 | 33 |
| d w — min | 38 | 42.75 | 46.55 |
| e — min | 45.2 | 50.85 | 55.37 |
| m — max | 23.8 | 25.6 | 28.7 |
| min | 22.5 | 24.3 | 27.4 |
| m w — min | 18 | 19.44 | 21.92 |
| s — max=nominal size | 41 | 46 | 50 |
| min | 40 | 45 | 49 |
| Attribute | M36 | (M39) | M42 |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 3 | 3 | 3 |
| Fine thread-2 | - | - | - |
| c — max | 0.8 | 1 | 1 |
| min | 0.2 | 0.3 | 0.3 |
| d a — max | 38.9 | 42.1 | 45.4 |
| min | 36 | 39 | 42 |
| d w — min | 51.11 | 55.86 | 59.95 |
| e — min | 60.79 | 66.44 | 71.3 |
| m — max | 31 | 33.4 | 34 |
| min | 29.4 | 31.8 | 32.4 |
| m w — min | 23.52 | 25.44 | 25.92 |
| s — max=nominal size | 55 | 60 | 65 |
| min | 53.8 | 58.8 | 63.1 |
| Attribute | (M45) | M48 | (M52) |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 3 | 3 | 4 |
| Fine thread-2 | - | - | - |
| c — max | 1 | 1 | 1 |
| min | 0.3 | 0.3 | 0.3 |
| d a — max | 48.6 | 51.8 | 56.2 |
| min | 45 | 48 | 52 |
| d w — min | 64.7 | 69.45 | 74.2 |
| e — min | 76.95 | 82.6 | 88.25 |
| m — max | 36 | 38 | 42 |
| min | 34.4 | 36.4 | 40.4 |
| m w — min | 27.52 | 29.12 | 32.32 |
| s — max=nominal size | 70 | 75 | 80 |
| min | 68.1 | 73.1 | 78.1 |
| Attribute | M56 | (M60) | M64 |
|---|---|---|---|
| P — Pitch — Fine thread-1 | 4 | 4 | 4 |
| Fine thread-2 | - | - | - |
| c — max | 1 | 1 | 1 |
| min | 0.3 | 0.3 | 0.3 |
| d a — max | 60.5 | 64.8 | 69.1 |
| min | 56 | 60 | 64 |
| d w — min | 78.66 | 83.41 | 88.16 |
| e — min | 93.56 | 99.21 | 104.86 |
| m — max | 45 | 48 | 51 |
| min | 43.4 | 46.4 | 49.1 |
| m w — min | 34.72 | 37.12 | 39.28 |
| s — max=nominal size | 85 | 90 | 95 |
| min | 82.8 | 87.8 | 92.8 |
Materials
- Material and property class specified per RFQ — state the mating bolt grade and pitch at quotation
Ordering & documentation
Documents
Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.
Quotation
- The fastener family (ISO 8673 Hex Regular Nuts (Fine Pitch)) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
- Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
- Quantity per size and your target delivery date.
- Destination country, and any required documents (for example a mill test certificate) so the quote includes them.
Sample & supply
Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.
Storage & shipping
Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.
Frequently asked questions
How do I order the right fine pitch on an ISO 8673 nut?
The size alone is not enough — fine-pitch series carry two pitches at many diameters. M10 exists as 10×1.25 and 10×1; M12 as 12×1.5 and 12×1.25; M20 as 20×2 and 20×1.5. A nut that fits the bolt blank will still jam if the pitch is wrong, and the collected table prints both options per size, so read the P rows first and name the pitch explicitly (M12×1.25, not "fine M12") on the RFQ. One transcription note: the collected page prints the second pitch row with the minus sign merged into the value ("-1.25"), a quirk of the source kept verbatim in the tables and disclosed in the unit note — treat the digits after the minus as the pitch and confirm against the mating screw before release.
What is the MOQ and lead time for this nut type?
The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Common sizes in this nut type are widely stocked; confirm the exact schedule against quantity and size mix at quotation.
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support