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Tri-Groove Tamper Proof Security Nuts Zamak 5 Zinc 5/16'-18 - Qty 100

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$166.30

$ 65 .99 $65.99

In Stock

About this item

  • High quality tamper proof security nuts
  • Tri Groove Security Nuts are made of Zamak 5 Zinc Alloy (95% Zinc, 4% Aluminum, 1% Copper). Zamak is an alloy of Zinc and Aluminium, sometimes also incorporating Magnesium and Copper.
  • The added copper in Zamak 5 increases the strength, hardness, and corrosion resistance of the alloy, but reduces its ductility and dimensional accuracy compared to other Zamak Alloys.
  • Tri Groove nuts are also referred to as T Groove, Trident Drive and Coned Trident Drive Nuts.
  • May only be installed and remove using tri groove or trident drivers or sockets - Sold Separately


Product Description

  • Tapered diameter resistant to gripping devices
  • Driven by three grooves on the outside of the nut
  • They are also known as Trident Drive Nuts, T-Groove Nuts, and Tri Groove Nuts
  • Installed using a special tri groove socket
  • Zamak 5 Zinc Alloy
  • Commonly used on boats, docks, piers and pools

Tri Groove security nuts feature a tapered diameter, making the nuts resistant to gripping devices. They are installed using a special Tri Groove socket, which grips the indentations along the outside of the fastener to turn the nut along a thread.

Tri Groove Nuts are commonly used with driver-less fasteners, such as carriage bolts or concrete anchors for a secure assembly. If the nut is not easily accessible, the fastener assembly will be harder to be tampered with. Security Nuts are commonly used in public outdoor applications including campsites, parks, playgrounds, benches, cars and roof top tents.

Tri Groove Security Nuts

tri groove nuts

Zamak 5 Zinc Alloy

Tamper Proof Nuts in this selection are made of zamak 5 zinc alloy. Zamac Zinc Alloy, a metal made of Zinc, Aluminum, Magnesium and Copper. Zamac Zinc alloy is designed to be durable and retain its strength and hardness over time, which adds to the benefits of tamper proof fasteners since they are suitable for long lasting applications.

tamper proof nut

Tamper Resistant Design

Tri Groove Nuts are circular and tapered making them extremely resistant to gripping devices. They require a special socket to grip the three indentations along the side of the nut to be installed.

tri groove security nuts

Common Applications

Because of their tamper resistant design, Tri Groove Nuts are commonly used in public applications including campsites, parks, playgrounds, benches, cars and roof top tents.


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