Brass Cup Square Bolts (DIN 603)

Brass Cup Square Bolts, according to DIN 603 / ISO 8677, feature a large rounded head with a square section positioned underneath.

Otherwise known as Brass Carriage Bolts or Brass Mushroom Head Square Neck Bolts, these components are often found in woodworking applications – used to join metal to wood. However, the machine thread makes cup square bolts suitable for metal to metal joins.

They require a pre-drilled hole for installation and are typically used alongside Brass Hex Nuts and Brass Washers. The nut is tightened against the washer using a spanner or wrench, which fastens the material onto the bolt.

The square section under the head digs into the material to prevent the bolt from turning. This square neck can also fit into a square hole to create a self-locking effect.

Brass Cup Square Bolts host a gold-like appearance for decorative applications, while the smooth drive-less head offers an aesthetically pleasing finish.

Available at Fastenright in thread sizes M5 to M8, with lengths up to 60mm. Optional thread locking patches are available on request for additional vibration resistance.

Non-standard sizes, materials and finishes are available to order as specials, including small volume manufacture, modifications and bespoke parts made to drawings. Minimum order quantities apply.

Our full range of Brass Fasteners can be found here.

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= Available Size not listed? Please contact us – we may be able to provide it.