Category: Screws

Salient Features of Clutch Head Screws

If you happen to see some kind of odd bow-tie shaped screw slots on your door or window pane, you’ve probably discovered the clutch head screws.  Such fasteners were extensively used in the auto industry from the 1940s through the 1960s. In 1970s, few of these screws also paved their way into travel trailer manufacturing industries as well.

10X High security clutch screws

Clutch head screws are also known as One Way Screws and ‘Security Screws‘. These specially designed fasteners are used for lasting installations. These are easy to use and can be installed using a normal screwdriver. The head of such kind of fastener features a normal drive and slanted rear face, which prevents the screwdriver from applying torque when trying to loosen these fasteners.

Once implanted, these rivets require typical drilling application for removal from the holes. However, you can even fetch for a special kind of driver bit to undo them.

Steel Clutch Head screws

In order to unscrew these rivers, you’re required to use a screwdriver bit of the same shape and size. The clutch head one way screws can be unscrewed in the clockwise direction by using a standard slotted screwdriver. This drive system was probably the worlds first security recess.

Unique Design

This unique feature enables such screws to be tamper-proof, thereby enhancing the security of your house and lessening the risk of robbery and making it impossible for the intruders to tamper the screws. Due to their unique design, there are even ideal for higher torque applications.

Clutch head with a hole for screw Driver

Thus, these fasteners are also referred as Jail Head. They are usually self-tappers and are used in applications jail cell hinges and even in domestic window locks and exposed door lock screws.


Standard Clutch Head

Standard Clutch Heads of screws

The clutch head screws are usually of two types: type A and type G. The type A is also known as a standard clutch and usually resembles a bow tie. And the type G resembles a butterfly.

Type G Clutch Head of a screw

These are zinc plated hardened steel and cannot be removed once they are installed. Besides, the countersunk clutch head screws can only be opened by a flat head screw driver


The type A screws were widely used earlier and were commonly seen in 1940s’GM automobiles, including trucks and buses. And the type G rivets are commonly used in the construction of mobile homes and recreational vehicles. You can even find them in your windows and doors, if they’re installed with some odd bow-tie shaped screw slots.

Special features of Clutch Head screws

These are ideal for

  • Public access wooden windows & doors
  • Seating & fencing
  • Prison fittings & fixtures
  • School & college fixings & fixtures
  • Also used in timber applications

Added Benefits

A police survey shows that around 30% of the intruders gain access to the houses through windows. Therefore, it’s utmost necessary to keep your windows secured.

Key-Rex Shape Security fastner

Beat the thieves with the clutch head screws!  

Their ‘one way’ design lets you fasten these screws with an ordinary Slotted screwdriver, but unscrewing them is virtually impossible. Hence, these can be of great help, as their unique features make it impossible for them to be unscrewed using a driver, instead a driller is required to undo them.

There’s another kind of screw known as A2 clutch head round wood screws.

Self tapper A2 Clutch Head round Wood screws

These fasteners are also known as Clutchless Screws and are made up of A2 stainless Steel.

These types of hardened steel self tapping screws can be used with various materials including wood, plastic and as a self tapping screw.


5 Inch construction screw

  • These fasteners are mostly used by the police and councils to secure number plates
  • Construction Security Screws
  • Sign Security

Now Get Rid of Squeaky Floor with Plywood Screws

Plywood screws, which are also known as chipboard screws are self-tapping screws, featuring thin shaft and coarse threads. These fasteners are made up of either wood dust or wood chips and resin, and as the name suggests, these screws are mainly in plywood and other soft wood surfaces.

These rivets are made to clinch this composite surface, so as to withstand loosening. The screws firmly hold either two plywood or any chipboard to other materials, say natural wood.

Apart from wooden works, these screws are highly recommended for squeaky floors as well. Recently one of our esteemed clients faced an issue with pressboard sub-flooring in his 20 years old house. While his upstairs flooring was creaking under the carpet, the downstairs floors jolt the entire house whenever stepped on promptly.

His main concern was to stop those high-pitched annoying sound and if he should go for another layer of plywood over the existing flooring? He was also interested in replacing the entire floor.

Playwood Screws for wood floors

So, this is what we had suggested him. Read on!

Instead of spending huge bucks in replacing the entire flooring, you can always go for an additional layer of plywood, which will definitely resolve all those issues. We highly recommend you to go for thicker material, as thicker the size would be, the degree of sound transmission would be reduced to more extent.

And yes, it’s always possible to fasten the existing wooden surface with the new layering. You’ll have to mark out the old nailing patterns, which should be in a gap of minimum 16 inches. Our aim should be enabling every new fastener with a supporting beam. By doing this, the squeaks will be reduced to a great extent and will even laminate properly the new layers along-with the base.

The plywood screws are the most ideal supplies required for fastening and you can even go for gluing, thereby strengthening the grip even more.

Different Sizes Of Play Wood Screws

In the meanwhile, do not forget about the sap, which pulls this surface up. So, better fasten it with those screws.

And do not try compromising with the quality of the screws, as this is definitely not a place to think about cost-cutting. So purchase the plywood screws in ample quantity and insert screw at every 4-6 inches of gap at the seams and at every 6-8 inches of gap in the field.

This is indeed an effective method, giving away long lasting results.

Much better looking wood floor with playwood screws

If your plywood is of 5-8 inches thick then you should consider those screws, which are at least 2 and 1/2 inches long, so that they can get a nice grip. However be warned that you don’t have any radiant heating line or plumbing beneath this surface.

We suggest you to go for an half inch plywood for the layering and you can even bowl over the seams from the existing surface. You can go cheap on the facings for the plywood to save from the recent hike in their pricing. For instance, you can go for CCX PTS, which exactly works as the ‘A’ grade material or you can even opt for OSB, which works well under the carpet.

The rooms with carpets need a little adjustment, as you would have to manage with the closets and swing doors for proper installation. You need to build a carpet shelf by raising the level of the carpeted areas.

But the major problem arises in areas, where you’re thinking of installing vinyl or linoleum flooring. For this, you’ll need a third layer of chipboard or particle board and so also the have to determine the size and thickness of plywood screws.

Not to mention, stairs are another nightmare. You can easily face trip hazards and in order to prevent this, you should confirm that the building code should have a minimum gap of at least 3-8 inches between the stairs, but the height should not exceed above 8.

Installing ITW Buildex Cement Board Screws

It is always necessary to use the exact type of fastener, say screws in certain conditions, so as to make sure that the installation procedure is executed effectively. And moreover, in the long run the correct usage of screw keeps it firmly fastened to the surface. You should always go for a company, say ITW Buildex, which has been in the hardware supply industry for over four decades, consistently working on enhancing its quality and services.

There are various types of screws available in the market, required for various kinds of jobs. The concrete screw is a very special type of fastener, specially designed to pierce its own threads into an already drilled hole on the surface made up of concrete, block, brick etc. The brand name Cement Board & Fiber Cement Board Screws is popular product, being sold over under this banner.

It was launched in early 80s and was highly popular because of its functionality even when there was less to no option for online branding. Such kind of screw can be easily installed and features enhanced pull-out shield and durable fixing values.

Cement Board & Fiber Cement Board Screws
In the concrete planting industry, the threads of such kinds of metal pieces are popularly called as “High-Low” screws. The threads of such screws enable quick dust removal during the installation process. Such strands also enable the fasteners to pierce in consistently, thereby giving high standard performance. The removal of dirt is relevant, as the dust present in the hole may interfere in the screwing process. Therefore, you should make sure that you’ve removed the dirt from the hole as well as from the thread.

Installing Cement Board ITW Buildex Screws

The installation procedure is quite simple. It can be done in three simple steps:

By using an accurate sized carbide capsized ashlar bit and a hammer drill, you can now drill a pilot hole of about 1/4th inches deep than the suggested anchor fastening

Now you need to clear the hole of the entire fragments

Now by using a standard drilling machine along-with an appropriate Phillips socket/hex, you can insert the metal screw into the already drilled hole until this fastener is completely pierced

You should be rather careful and should take care that you have not over-tightened the ITW Buildex screw, as this will cause the fastener to spin within the hole, thereby stripping the threads.