Countersunk Shear Bolt Security Anchors host a conical-shaped head, with a hexagonal nut at its peak, meaning that they can be tightened using a standard spanner socket.
By fully tightening the hexagon nut section until the pressure applied surpasses the maximum torque limit, this results in the hexagonal part of the countersunk bolt to snap or break off and leave a plain tamper-resistant flat head.
Shear Bolt Security Anchors are suitable for higher torque applications and are one-way permanent fixings, making them ideal for applications where maintenance is not required, and they provide a high level of resistance to vandalism and theft – which is typically why they can be found in prisons, perimeter fencing, railings, security windows and door frames.
They are referred to by a range of different names; including Snap Off Nut Anchors, Break Away Nut Anchors, Break Away Head Anchors, Shear Bolt Anchors, Security Snap Off Anchors and Perma Bolt Anchors.
Available as standard in Stainless Steel from Fastenright, in lengths and diameters ranging between M8 x 65 and M8 x 85.
Non-standard sizes and materials are available to order as specials, including custom parts made to drawings.
|Size (DxL)||Hole Size (D1)||Min Hole Depth (h/d min)||Max Fixture Thickness (f/t max)||Spanner Size (sp)||Recommended Torque|
|M8 x 65||10mm||55mm||5mm||15mm||19 n/m|
|M8 x 85||10mm||55mm||25mm||15mm||19 n/m|