Carriage Bolt

18-8 stainless steel carriage bolts are made from one of the following austenitic alloys: 302 HQ, 303, 303Se, 304, XM7, all of which are characterized as having a chromium content of 17-19% and nickel content of 8-10%.

Carriage Bolts are primarily used in wood projects.

A carriage bolt, coach bolt or round head square neck bolt is used through iron strengthening plates on either side of a wooden beam. It is commonplace though to use them on bare timber, the squared section giving enough grip to prevent rotation. Carriage bolts are extensively used in security fixings where the bolt must only be removable from one side. The smooth domed head and square neck below prevent the carriage bolt from being unlocked from the insecure side.