DIN 603 Coach Bolts (Cup Head Square Neck)
M5 - M16
Steel 4.6Grade 8.8GalvanisedStainless steel A2Stainless steel A4
≡ ISO 8677
We supply DIN 603 coach bolts in steel grades 4.6 and 8.8, galvanised finishes and A2/A4 stainless steel, from M5 to M16. The domed head has no drive: the square neck below it pulls into timber or a square punched hole and holds the bolt still while the nut is tightened from the other side.
Also known as: coach bolt, cup square, carriage bolt, cup head square neck bolt, mushroom head bolt.
DIN 603 dimensions
| Diameter | Pitch | Head diameter | Head depth | Width of square | Depth of square |
|---|---|---|---|---|---|
| M5 | 0.8mm | 13.55mm | 3.3mm | 5.48mm | 4.1mm |
| M6 | 1.0mm | 16.55mm | 3.88mm | 6.48mm | 4.6mm |
| M8 | 1.25mm | 20.65mm | 4.88mm | 8.58mm | 5.6mm |
| M10 | 1.5mm | 24.65mm | 5.38mm | 10.58mm | 6.6mm |
| M12 | 1.75mm | 30.65mm | 6.95mm | 12.7mm | 8.75mm |
| M16 | 2.0mm | 38.8mm | 8.95mm | 16.7mm | 12.9mm |
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