Cup Sq Hexagon Bolts & Nuts ZP

The cup square hexagon bolt - better known in the UK as a coach bolt - is the timber fastener of choice for applications where a flush, dome-headed fixing is needed on the visible face and a nut secures from the back. At the DIY Hardware Store, our zinc-plated cup square bolts and matching nuts are available in the sizes most commonly used in timber gate construction, fencing, garden furniture, and structural joinery.

The design is elegantly simple: a low, domed head sits neatly on the surface with no drive recess visible, while a square shoulder just below the head bites into the timber as the nut is tightened, preventing the bolt from rotating during installation. This means only a single spanner or socket is needed to tighten the fixing - no need to hold the head with a second tool.

Zinc plating provides adequate corrosion protection for outdoor use in sheltered conditions. For fully exposed or ground-contact applications, hot-dip galvanised or stainless steel coach bolts are a more durable specification.

  • Dome head with no visible drive recess - clean surface appearance
  • Square shoulder locks bolt against rotation in timber
  • Single-spanner tightening - no second tool required
  • Used in timber gates, fencing, and garden furniture
  • Zinc-plated finish for outdoor sheltered use
  • Available in standard diameters and lengths