ISO 7380-1 Hexagon Socket Button Head Screws
ISO 7380-1 hexagon socket button head screws M3 to M16 — the flangeless low-domed socket screw — with the full collected per-size table: thread pitch, head and shank tolerances, socket sizing, minimum tensile loads per property class (8.8/10.9/12.9 and 70/80 as printed) and thread length b, a strength-tabulated counterpart to the socket cap screw line.
Last updated: 2026-11
Specifications
The ISO 7380-1 button head is what a socket cap screw becomes when the head must disappear sideways rather than downward: a low, wide dome with a hexagon socket, trading head height and bearing diameter against tensile capacity relative to the cap-screw line. The tabulated data is unusually complete for a screw of this type — it tabulates not just geometry (thread pitch P, head diameter d k max/min, shank d s max/min, head height k, socket depth t, across-flats s nominal with tolerances and across-corners e min) but a minimum tensile load row per diameter for five property-class printings: 8.8, 10.9 and 12.9 carrying a superscript ②, and 70 and 80 carrying a superscript ③. No legend is published for those markers, so this page reproduces them verbatim rather than interpreting — read the row that matches the class your drawing calls out. The numbers tell the engineering story directly: at M6 the 8.8 row carries 12,900 N against 19,600 N at 12.9, and the stainless-class rows carry proportionally less. The series runs M3 to M16, with thread length b growing from 18 to 44 mm. One designation note: "-1" is the flangeless version — where a flange or collar under the head is part of the callout, that is the -2 designation, and the security variant with a pin-in-socket drive is covered by the ISO 7380-2 page on this site.
| Standard | ISO 7380-1 — hexagon socket button head screws ("-1" is without a flange/collar; the flanged version is the -2 designation) |
|---|---|
| Series | M3, M4, M5, M6, M8, M10, M12, M16 |
| Tabulated geometry | Per size: pitch P, head dia d k max/min, shank dia d s max/min, head height k max/min, socket depth t min, across-corners e min, socket across-flats s nominal/max/min |
| Minimum tensile load | Tabulated per size per printed class row — 8.8 ② / 10.9 ② / 12.9 ② / 70 ③ / 80 ③ (3220–154,000 N across the series); the ②/③ markers are reproduced as printed, no legend is published |
| Thread length b | 18 mm (M3) to 44 mm (M16) as tabulated |
| Family notes | Flanged counterpart = ISO 7380-2 designation family (security pin-in-socket variant page on this site); socket cap screw counterpart = DIN 912 / ISO 4762 |
| Nominal thread | P — pitch (mm) | d k max (mm) | d k min (mm) | d s max (= nominal) (mm) | d s min (mm) | k max (mm) | k min (mm) | t min (mm) | e min (mm) | s nominal (mm) | s max (mm) | s min (mm) | Min tensile load 8.8 ② (N) | Min tensile load 10.9 ② (N) | Min tensile load 12.9 ② (N) | Min tensile load 70 ③ (N) | Min tensile load 80 ③ (N) | b — length of thread (mm) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.5 | 5.7 | 5.4 | 3 | 2.86 | 1.65 | 1.4 | 1.04 | 2.303 | 2 | 2.08 | 2.02 | 3220 | 4180 | 4910 | 2810 | 3220 | 18 |
| M4 | 0.7 | 7.6 | 7.24 | 4 | 3.82 | 2.2 | 1.95 | 1.3 | 2.873 | 2.5 | 2.58 | 2.52 | 5620 | 7300 | 8560 | 4910 | 5620 | 20 |
| M5 | 0.8 | 9.5 | 9.14 | 5 | 4.82 | 2.75 | 2.5 | 1.56 | 3.443 | 3 | 3.08 | 3.02 | 9080 | 11800 | 13800 | 7950 | 9080 | 22 |
| M6 | 1 | 10.5 | 10.07 | 6 | 5.82 | 3.3 | 3 | 2.08 | 4.583 | 4 | 4.095 | 4.02 | 12900 | 16700 | 19600 | 11200 | 12900 | 24 |
| M8 | 1.25 | 14 | 13.57 | 8 | 7.78 | 4.4 | 4.1 | 2.6 | 5.723 | 5 | 5.14 | 5.02 | 23400 | 30500 | 35700 | 20400 | 23400 | 28 |
| M10 | 1.5 | 17.5 | 17.07 | 10 | 9.78 | 5.5 | 5.2 | 3.12 | 6.863 | 6 | 6.14 | 6.02 | 37100 | 48200 | 56600 | 32400 | 37100 | 32 |
| M12 | 1.75 | 21 | 20.48 | 12 | 11.73 | 6.6 | 6.24 | 4.16 | 9.149 | 8 | 8.175 | 8.025 | 53900 | 70200 | 82400 | 47200 | 53900 | 36 |
| M16 | 2 | 28 | 27.48 | 16 | 15.73 | 8.8 | 8.44 | 5.2 | 11.429 | 10 | 10.175 | 10.025 | 100000 | 130000 | 154000 | 87900 | 100000 | 44 |
Materials
- Steel, property classes 8.8 / 10.9 / 12.9 (per the collected tensile-load rows)
- Stainless-class rows 70 / 80 (per the collected tensile-load rows, markers as printed)
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 7380-1 Hexagon Socket Button Head Screws) 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
Button head or socket cap screw — what does the choice cost?
Height versus strength. The button head is the lower-profile head — that is why it wins inside slides, clamped covers and flush-clearance envelopes — but the wider, thinner head carries a lower tensile load than the cap-screw head, and the collected table quantifies it per class and size — at M8, for example, the strongest printed row is 35,700 N at 12.9. If the joint was sized for a cap screw, do not substitute a button head without re-checking that row.
What should an RFQ for ISO 7380-1 screws state?
The designation (ISO 7380-1 for the flangeless head), thread size M3–M16 and length, property class — 8.8/10.9/12.9 steel or the 70/80 stainless rows — finish, any certificate requirement such as a mill test report per EN 10204 3.1, and quantity per size. Minimum tensile loads per row are in the table on this page; per-length availability and commercial terms follow the quotation.
What is the MOQ and lead time for these screws?
Minimum order quantity is 10,000 pieces per item. Stocked sizes ship in 3–7 days; non-stock diameters, lengths or finishes are quoted with a confirmed schedule. Common sizes in this designation are widely stocked — confirm the exact schedule against quantity and size mix at quotation.
Related knowledge
- Thread-Forming vs Thread-Cutting vs Thread-Rolling Self-Tapping Screws: What the Evidence Settles on Base Material
- Screw Family Selection by Base Material: Wood, Machine and Self-Tapping Threads, Engagement and Coating
- Hex Bolts vs Socket Head Cap Screws: What the Evidence Settles on Strength, Clearance and Cost
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