Driven with a 2.5 mm hex key, the M4 flanged button head screw (ISO 7380-2) has a head 6.84 to 7.2 mm across and 1.95 to 2.2 mm tall. Its M4 × 0.7 thread comes in 4 lengths from 8 to 16 mm, each as simplified and threaded STEP.

How these parts are made, and what the levels mean: read the method
- Also searched as: M4 bolt, M4 x 8 to M4 x 16 bolts
- Model id:
iso7380-2-m4
- Standard: ISO 7380-2:2022 · thread M4 × 0.7, ISO metric coarse, right hand
Lengths
Dimensions

| Symbol | Name | min | nom | max | Modeled | Rule | Level |
|---|
| P | Thread pitch | | 0.7 | | 0.7 | nominal | L2 |
| b | Thread length | | 20 ref | | 20 | reference value | L1 |
| c | Collar height | 0.65 | | 0.8 | 0.725 | midpoint of min–max | L2 |
| da | Transition diameter | | | 4.7 | 4.7 | single limit (max), modeled at the limit | L2 |
| dc | Collar diameter | 8.82 | | 9.4 | 9.11 | midpoint of min–max | L2 |
| dk | Head diameter | 6.84 | | 7.2 | 7.02 | midpoint of min–max | L2 |
| dL | Head top diameter | | 3.8 ref | | 3.8 | reference value | L2 |
| ds | Shank diameter | 3.82 | | 4 | 3.91 | midpoint of min–max | L2 |
| dw | Bearing face diameter | 7.94 | | | 7.94 | single limit (min), modeled at the limit | L2 |
| e | Socket width across corners | 2.87 | | | 2.87 | single limit (min), modeled at the limit | L2 |
| k | Head height | 1.95 | | 2.2 | 2.075 | midpoint of min–max | L2 |
| rf | Head dome radius | 4.2 | | 4.6 | 4.4 | midpoint of min–max | L2 |
| rs | Underhead fillet radius, plain shank | 0.2 | | | 0.2 | single limit (min), modeled at the limit | L2 |
| rt | Underhead fillet radius, fully threaded | 0.4 | | | 0.4 | single limit (min), modeled at the limit | L2 |
| s | Socket width across flats | 2.52 | 2.5 | 2.58 | 2.55 | midpoint of min–max | L2 |
| t | Socket depth | 1.3 | | 1.65 | 1.475 | midpoint of min–max | L2 |
| wb | Wall thickness | 0.3 | | | 0.3 | single limit (min), modeled at the limit | L2 |
| P | Coarse thread pitch | | 0.7 | | 0.7 | nominal | L1 |
| tap_drill | Tap drill diameter | | 3.3 | | 3.3 | nominal | L1 |
| d1 | Basic minor diameter | | 3.2422276 | | 3.2422276 | nominal | L1 |
| ch_angle | Chamfered end angle | | | 50 | 50 | single limit (max), modeled at the limit | L2 |
| dh_fine | Clearance hole, fine series | | 4.3 | | 4.3 | nominal | L1 |
| dh_medium | Clearance hole, medium series | | 4.5 | | 4.5 | nominal | L1 |
| dh_coarse | Clearance hole, coarse series | | 4.8 | | 4.8 | nominal | L1 |
Thread and holes
- Tap drill: 3.3 mm (method: d − P), L1, sources amesweb-tap-drill, rule-tap-drill.
- Clearance hole (ISO 273): close 4.3, normal 4.5, loose 4.8 mm (L1: fine, medium and coarse series (albany-clearance, wikipedia-de-clearance)).
Drawing

As a PDF: CC-ISO7380_2-SZ-M4.pdf.
The M4 is number 2, counting from the smallest, of the 5 ISO 7380-2 flanged button head screws published here, from M3 to M8.
- Thread pitch (P): 0.7 mm on the M4 flanged button head screw, against 0.5 mm on the M3 and 0.8 mm on the M5.
- Thread length (b): 20 mm (reference) on the M4 flanged button head screw, against 18 mm (reference) on the M3 and 22 mm (reference) on the M5.
- Collar height (c): 0.65 to 0.8 mm on the M4 flanged button head screw, against 0.55 to 0.7 mm on the M3 and 0.8 to 1 mm on the M5.
- Transition diameter (da): up to 4.7 mm on the M4 flanged button head screw, against up to 3.6 mm on the M3 and up to 5.7 mm on the M5.
- Collar diameter (dc): 8.82 to 9.4 mm on the M4 flanged button head screw, against 6.32 to 6.9 mm on the M3 and 11.1 to 11.8 mm on the M5.
- Head diameter (dk): 6.84 to 7.2 mm on the M4 flanged button head screw, against 4.9 to 5.2 mm on the M3 and 8.44 to 8.8 mm on the M5.
- Head top diameter (dL): 3.8 mm (reference) on the M4 flanged button head screw, against 2.6 mm (reference) on the M3 and 5 mm (reference) on the M5.
- Shank diameter (ds): 3.82 to 4 mm on the M4 flanged button head screw, against 2.86 to 3 mm on the M3 and 4.82 to 5 mm on the M5.
Other sizes
Documents
Sources
albany-clearance, amesweb-tap-drill, bossard-bn30104-lengths, fasten-it-iso7380-2, fasteners-eu-iso7380-2, globalfastener-iso7380-2, iso4753-2011-sample, iso7380-2-2022-sample, reca-iso7380-2, rule-basic-minor, rule-iso7380-2-u-head, rule-tap-drill, wikipedia-de-clearance, wikipedia-iso261. Full citations: the method page and this size's datasheet.
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