Coach Bolts

Often called carriage bolts or cup square hex bolts, coach bolts have a round head with a square underside.

Our zinc plated coach bolts come complete with a matching hex nut (for stainless steel coach bolts please order the nuts separately).

Coach bolts are available in a range of sizes. All have metric coarse threads. They are most commonly used in the construction and timber trades.

Coach bolts are often confused with coach screws, which are actually hexagon headed woodscrews. Coach Bolts are usually made from mild steel in strength grades 4.6 or 4.8 and our BZP stock is usually marked with the manufacturer's I.D. and the strength grade on the head.

Interesting fact – the often-used name carriage bolt dates back to the time of horse-drawn carriages, where these bolts were used to fix metal straps to the wood with the square head holding the bolt firm as the night was tightened!