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Clutch Head Security Barrel Nuts & Sex Bolts

Tamper Proof Clutch Head Security Sex Bolts Protect Against Vandals and Thieves

  • Medium Security Resistance
  • Permanent one-way drive
  • Usable for medium torque applications
  • Ideal for use in architectural staircasing and balustrading

A security sex bolt is a tamper-proof adaptation of the commonly known sex bolt, also known as a barrel nut, barrel bolt, Chicago screw, architectural bolts or post and screw.

This is a type of tamper-proof security fastener which has a barrel-shaped flange and protruding boss that is internally threaded. The boss sits within the components being fastened, and the flange provides the bearing surface.

The security sex bolts, including a male and female bolt, and the accompanying tamper-proof security machine screw sit flush on either side of the surfaces being fastened.

It is often chosen because of its low profile compared to other fasteners. It has a built-in security drive feature to aid in tightening the fastener.

They can also be referred to as a sleeve nut within the industry.

  • Male screws are available with or without shoulders.
  • All parts are matched for a finished appearance.
  • Both female and male bolts feature the security drive.
  • Head dimensions for both male and female parts are matched.
  • Button Head, Truss Head and Countersunk head available.

Can be manufactured in Steel or Stainless steel depending on individual customer requirements.

Non-standard sizes and materials are available to order as specials, including custom parts made to drawings.


Clutch Head Barrel Nuts Technical Drawing


Imperial Technical Information & Available Sizes
Thread Diameter 10 – 24 UNC
A (mm) 10.9<
B (mm) 12.6< (1/2″) 15.9< (5/8″)
C (mm) 6.3<
Available Sizes 10 – 24 UNC
1/2″ black icon image
5/8″ black icon image
black icon image = Available
Size not listed? Please call to discuss – we may be able to provide it.

Clutch Head One Way Barrel NutClutch Head One Way Male ScrewClutch Head One Way Sex Bolt Sets