Carriage Bolts
Domed-head carriage bolts with a square neck that locks into the hole so the bolt can't turn while the nut is tightened.
Manufactured by Uvi Tech Fit in Kundli, Sonipat, India.
Or message us on WhatsAppDIN 603, ISO 8677
Overview
Carriage bolts have a smooth domed head and a square neck under it that locks into the mating slot or timber, so the bolt cannot spin while the nut is tightened from the other side. They suit wood-to-metal joints, channels, guards, and fabrication where a clean tamper-resistant face is wanted.
Also known as: coach bolt, cup head square neck bolt, round head square neck bolt.
Related parts: Hex Head Bolts, Flange Bolts, Hex Flange Phillips
Used in
- Wood-to-metal joints
- Channel and framework assemblies
- Guards and covers
- Furniture and fixtures
- Fabrication and site assemblies
- Transport and body-building hardware
Dimensions
Mushroom head square neck bolt (DIN 603)
| Size | Head dia. dk | Head height k | Square neck (max) |
|---|---|---|---|
| M5 | 13.55 | 3.3 | 5.0 |
| M6 | 16.55 | 3.88 | 6.0 |
| M8 | 20.65 | 4.88 | 8.0 |
Reference values from the standard, in mm. Parts are made to your drawing or the standard you name; lengths up to 100 mm.
Parts are checked at each stage with vernier calipers, micrometers and visual inspection. Material and test reports can be arranged on request.
Request a Quote
Give size, length, material, finish and quantity. For a custom part, attach a drawing or a photo of the sample.
Questions
Will the square neck hold in metal?
Yes, if the metal part has a square hole or slot. In timber the neck is pulled into a round hole as the nut is tightened.
Why use carriage bolts?
The smooth dome can't be gripped from outside, so the joint can only be undone from the nut side. Useful for guards, fences and outdoor frames.
Which finish for outdoor use?
Zinc-plated mild steel for sheltered use; stainless steel where the bolt is fully exposed.