Hy-Com Communications Ltd.

Tamper Resistant and Tamperproof Fasteners

Definitions

Tamper Resistant versus Tamperproof

Security screws fall generally into two categories: tamper resistant and tamperproof. The difference lies mainly in the availablilty of screwdriver bits for use with the screws.

Tamper Resistant

Tamper resistant fasteners are of a common configuration, such as Phillips, Torx®, or Hex that have pins or another simple mechanism to prevent "over the counter" screwdriver bits from being used to remove the screw. The common screwdriver bits can generally be converted with a little effort, such as by drilling a hole, or else the proper bits are available at selected hardware or tool outlets.

These screws are generally used where security is not the main concern, but rather where there is the need to prevent easy access.

Tamperproof

Tamperproof fasteners are not common at all. They have a unique shape and can even be one of a kind. To remove these screws, the exact key must be used. These are controlled by the manufacturer, and may even be licensed exclusively to a particular customer.

These screws are used in applications where security is the major concern.

In spite of making these screws in very difficult to remove configurations such as button head or countersunk, the security is not absolute. They can for example still be drilled out or ground off, depending on the choice of material used. This can be partly overcome by making the screws difficult to access. Hardened versions of the screws are available which will make drilling very difficult.

Also, no mounting solution is stronger than the surface to which the equipment is mounted. If, for example, a radio bracket is screwed to a plastic panel, using security screws will not be of much help, as the bracket could be pried out of the plastic in a few seconds with a prybar.


Securing Equipment the Easy Way

How It Works

To prevent theft of radios or unauthorized removal consider using simple and inexpensive tamper resistant or tamperproof screws. Often the radio mounting bracket screws are hidden under the radio, making them inaccessible. Securely mounting the bracket, and then using tamperproof screws to mount the radio in the bracket will make the radio almost impossible to remove without the proper screwdriver key bit. The weakest part of the installation becomes the part of the vehicle to which the bracket is attached.

The screws shown here are not just tamperproof. Because the screwdriver bit for these screws is uniquely manufactured, it is a high security locking system. The shape is not symmetrical or easy to distinguish and compromise. These screws are not an easy target or false security.


Additional Points

These screws have larger heads than normal to spread the friction load and thus prevent vibration loosening. This reduces the possibility of exposing an edge to locking pliers or a similar tool.

A chemical locking compound such as Permabond® MM115 or Locktite® 222 should be used rather than a lock washer to prevent vibration loosening. A lock washer would raise up the screw head, exposing an edge to locking pliers or a similar tool.

For product information or further pricing information please call or e-mail
sales@hy-com.com

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