Shear Nuts (Security Nuts)
Shear nuts are a permanent security fastener. The hex part of the nut shears off during installation leaving a cone designed to resist tampering and removal.
Materials & strength
Permanent anti-tamper design
The smooth cone left after installation is deliberately hard to grip, giving strong resistance to removal and interference.
Finishes for outdoor use
Galvanised and stainless options suit street furniture and other exposed fixings; zinc plated suits drier or indoor locations.
What is a shear nut?
A shear nut is a security nut with a cone-shaped base and a hexagon drive section above it. During installation the hexagon shears away, leaving a smooth tapered cone that offers almost nothing for a tool to grip.
How are shear nuts installed?
They are fitted with a standard spanner or socket like an ordinary nut; as tightening proceeds, the hexagon section shears off at a designed break point, leaving the cone in place. They are installed with standard hand tools.
Can shear nuts be removed?
They are designed as a permanent, tamper-resistant fixing: once the hexagon has sheared away, the remaining cone gives strong resistance to gripping and turning. Treat a shear-nut joint as permanent when specifying it.
Where are shear nuts used?
On fixings the public can reach or that must resist interference - street furniture, signage, grilles, fencing, cubicle hardware and plant in public areas.
What materials are shear nuts available in?
Shear nuts are available in galvanised steel, zinc plated steel and stainless steel across a wide range of metric sizes. Stainless or galvanised finishes are the usual choice outdoors.
Need Shear nut in a non-standard size or material?
Send us your drawing — specials quoted within 24 hours.