Versatile Choices for Every Project
Our carriage bolts are designed for reliability, appearance, and speed of install. The dome head sits flush for a snag-free finish, while the square neck locks into wood or pre-punched metal to prevent rotation as you tighten the nut. Choose lengths and diameters for light cabinetry up to heavy structural joins, then pick the finish that matches your environment and look.
Our carriage bolts combine a round, low-profile head with an under-head square neck that seats quickly and resists spin-out, so you can tighten from one side without holding the head. This makes them perfect for wood-to-wood, wood-to-metal, and light metal-to-metal connections where a clean face and dependable clamp force matter. Use them in benches, decks, playgrounds, guard panels, sign frames, machinery enclosures, and architectural fixtures where you need strength with a finished look.
Complete your assembly with the right hardware: pair our carriage bolts with a Hex Nut for everyday builds, a Square Nut for a classic look and increased wrench contact in tight spaces, or a Hex Jam Nut when you need a low-profile lock against vibration.
DIN 603 Carriage Bolts
Our DIN 603 carriage bolts feature a smooth, dome-shaped head with a square neck beneath to stop rotation during tightening. They’re a go-to for wood and metal assemblies where you want a flush, tamper-resistant head and a clean finished surface. Use them in benches, decks, machinery guards, sign frames, fixtures, and anywhere a neat appearance meets dependable clamp force.
DIN 603MU is a modified take on the DIN 603 pattern, typically indicating manufacturer-specific tweaks for special applications. Expect the same dome head and square neck you rely on, with adjustments that can include thread length, tolerances, or finish options to fit production needs. If your project calls for a spec-driven alternative, our 603MU variants keep your line moving without compromising fit or function.
FAQs
What is the difference between a carriage bolt and a coach bolt?
In many regions, the terms are used interchangeably for a round, dome-head bolt with a square neck. Some catalogs use “coach bolt” as the traditional name in timber work, while “carriage bolt” appears more often in general hardware. Functionally, both secure materials using that square neck to prevent spin during tightening.
When should I use carriage bolts?
Choose them when you need a clean, low-profile head on the visible side and fast, one-wrench installation. They’re ideal for wood-to-wood, wood-to-metal, and light metal-to-metal joints with pre-punched square or round holes. They also help deter casual tampering because the head has no drive recess.
What is a carriage bolt used for?
Common uses include furniture assembly, decking and outdoor structures, equipment guards, handrails, signage, and fixtures. The square neck locks into the material so you can tighten the nut from the opposite side without holding the head. The result is a neat, durable joint with even clamping pressure.
Why are they called carriage bolts?
The name comes from their historic use in wooden carriage construction, where the smooth head protected surfaces and the square neck gripped timber. That same combination of clean looks and anti-rotation still makes them a favorite today. Our modern versions bring those roots into precise, production-ready hardware.
