| Item | Specification Details |
|---|---|
| Product Name | Carriage Bolt / Round Head Square Neck Bolt |
| Material | High Strength Carbon Steel Q235 |
| Surface Finish | Yellow Zinc Plated |
| Standard Sizes | M6, M8, M10, M12, M16; Custom thread length available |
| Structure | Large smooth round dome head + integrated square anti-rotation neck + full thread shank |
| Applicable Base | Timber, metal sheet, guardrail, garden furniture, agricultural machinery, playground equipment |
| Core Features | Smooth burr-free round head for safety, square neck locks workpiece to prevent bolt spinning, uniform full rolling thread, wide head for large contact area & pressure dispersion |
| Application Scenarios | Fence & guardrail assembly, outdoor wooden furniture fixing, farm equipment connection, timber-metal composite structure installation, public leisure facility construction |
| Custom Service | OEM & ODM, custom thread length, customized head diameter, special anti-corrosion surface treatment |
Carriage Bolt
Carriage Bolt, also known as round head square neck bolt, is a specialized fastener designed for wood-metal composite connections.
It features a wide, smooth domed round head that eliminates sharp edges to prevent scratches on users and matching materials. The square neck under the head is the key functional part: when inserted into pre-punched square holes of plates or brackets, the square neck embeds tightly into the workpiece to lock the bolt body completely, stopping rotation during nut tightening without holding the bolt with extra tools. The full precision rolling thread matches standard hex nuts and flat washers to deliver stable, long-lasting clamping force.
This carriage bolt adopts yellow zinc plating surface treatment, forming a dense anti-rust coating to resist oxidation and mild outdoor humidity, ideal for general outdoor and workshop use. Compared with ordinary hex bolts, its anti-rotation design and safe smooth head make it the preferred choice for outdoor public facilities and wooden structures.
All finished carriage bolts undergo tensile strength and thread precision testing before delivery, complying with construction and furniture fastening safety standards. Custom thread lengths and head sizes can be produced to fit different plate thicknesses and load requirements for bulk orders.
