Tamper proof screws are designed to be difficult or impossible to remove. In this article, we look at some of the most common types and how they work.
Tamper proof screws designed to prevent unauthorised removal or tampering. The use of tamper proof screws has increased in recent years to prevent theft, interference with fixtures and increasingly to prevent access to the working parts of mobile phones and other gadgets.
There are various levels of “tamper proof”. Some screws are secure enough to deter casual interference, others are almost impossible to remove without a specific driver. “One way” security screws are designed so that they cannot be unscrewed at all, and these are ideal for permanent fixings where no maintenance is likely to be required.
Some of the common tamper-proof screw types are listed below:
Pin Hex head screws: Conventional socket screws have a hexagonal recess and are fixed using a hex bit or allen key. Pin hex screws use a similar drive, the difference being that there is a pin inserted in the middle. This means that these fixings require a special tool to fix or remove them, as a conventional hex bit or similar tool would not work.
Pin TX screws: Like the Pin Hex, the Pin TX has a pin inserted in the recess of the drive, which in most typically a 6 lobe or Torx® drive, although an even more secure 5-lobe option is available. These screws also require a special tool to fix and remove them.
Sentinel screws: These are permanent fixings, with a unique drive design which can only be turned one way, so they can’t be unscrewed. They can be installed using a cross head or pozi driver and are easy to install, so suitable for large volume applications.
Clutch head security screws: These work in a similar way to Sentinel screws and can be installed with a standard slotted screwdriver. Again once this screw is fitted it cannot be unscrewed, making it a permanent or 1-way fixing.
2 Hole or Pig Nose screws. These screws have 2 holes drilled into the head (the appearance resembling a pig’s nose, hence the name) which need a special bit for fixing. This type of screw is used mainly where aesthetics are important.
Generally, tamper proof screws can be used as direct replacements for standard screws. There are available in a range of styles and sizes, so whatever the application, you should be able to find a suitable tamper-proof option. They are typically finished in A2 stainless steel, although other finishes are available.
Using tamper proof screws on products
Security Screws are certainly a worthwhile consideration in not just preventing theft, but also for manufacturers to prevent unwanted tampering of their products, e.g. for safety reasons.
It’s likely that you’ve seen various iterations of the following message featured in product instruction manuals for a range of gadgets: “Do not attempt to take this product apart, ensure that a qualified professional is sought”. This particularly features in electrical products where opening up the product could result in electric shock. The use of security screws is ideal for manufacturers of these types of product ensuring that it is made difficult for an end user to take the product apart.
Similarly, furniture manufacturers may wish to prevent furniture from being taken apart once it has been manufactured and is in the customer’s home. It may be intricate to put back together once removed and require a professional, or it may even compromise the safety of the furniture. Simply replacing standard fixings with security fixings will prevent the amateur user from tampering with it.
It may also be useful to employ tamper proof screws in products where you would like to be the only option for maintenance and repair. This would mean that users would not be able to attempt to fix their product, hence preventing them damaging the product further through attempting to fix internal mechanisms should things go wrong.
Premium security screws
Standard tamper proof screws are just that – they are highly resistant to tampering but a really determined person may be able to remove them.
For high security applications then a premium security screw is the best option. These have a more complex drive design and are installed and removed using a specialist, traceable tool. One example is the Tricone® Security Bolt which is unique to Fastenright and has a patented drive design, is very difficult for unauthorised users to remove and look really good too!
How to choose a tamper proof screw
When selecting a tamper proof screw there are several factors to consider such as:
- The level of security required
- Does the screw need to be removed at any time?
- Is a high torque fixing required – e.g. Pin Hex may be more suitable than say a 2-Hole
- Is the aesthetic appearance important?
There is a wide range of tamperproof screws available as machine screws (for pre threaded holes) and self tapping screws which create their own hole. They can also be supplied in round head, countersunk or button head configurations depending on the screw type.
With so much choice, if you don’t know exactly what type of fixing you need, talk to the experts at Fastenright and we will be happy to give any help or advice you may need.
Article originally written 21st November 2016. Fully reviewed and updated 26th November 2020.