Cup Head Bolt & Nut Galvanised ISO8678/AS1390

Cup head bolt and nut assemeblies are desgined for timber to timber or timber to steel connections. The square neck under the dome head prevents the bolt from turning in the pre-drilled timber hole. Cup heads are typically hammered in and tighten off with a spanner.

Not to be confused with a coach bolt which has a hex head and woodthread, cup head bolts (or carriage bolts as sometimes called) have a metric thread with the flat chamfered end. In most cases the bolt length will have a clear shank as the thread will only be required at the final 10 - 20mm of bolt length.