Self Tapping Screw – Flange Head – Zinc – Box 200

These flange head self tapping screws are manufactured to BS 4174 and available in a range of sizes to suit most general fixing applications. The cross recess AB type thread form cuts cleanly into sheet metal, plastic, and light gauge materials without the need for a pre-tapped hole. If you regularly reach for self tapping screws on site, the flange head design earns its keep by spreading the load over a wider area without needing a separate washer.

Each screw is case hardened, which means the outer surface is tough enough to resist shearing under load and handle excess torque without the head rounding off on you. That matters when you are driving screws at pace with a powered driver you want the fastener to hold firm, not twist apart halfway through a job.

Flange Head Self Tapping Screws: What the Design Does

The flange head is the key feature here. Unlike a standard pan head screw, the flange extends outward beneath the head and acts as a built-in washer. This spreads the clamping load across a broader surface area, which reduces the chance of the head pulling through thinner or softer substrates. It also gives a cleaner, more finished appearance on exposed fixings where a loose washer would look untidy or could work free over time.

The cross recess drive is compatible with standard PH2 and PZ2 bits, so there is no need for specialist tooling. The AB thread form has a sharp, self-cutting tip that starts cleanly without a pilot hole in most sheet materials, saving a step on repetitive work.

Zinc Plating and Corrosion Resistance

The zinc coating on these screws uses trivalent chromium (CR3) at 3 microns thickness. This is a RoHS-compliant finish that provides reliable protection against corrosion in general indoor environments and light external use. Trivalent chromium has replaced the older hexavalent chrome process across the industry due to its reduced environmental impact, without sacrificing the performance you would expect from a standard zinc plate.

For applications exposed to prolonged moisture, salt spray, or acidic environments, a stainless or high-zinc alternative would be more appropriate. For typical workshop, manufacturing, panel assembly, and interior construction use, this finish is more than adequate.

These flange head self tapping screws are sold in boxes of 200 and are available across nine size options ranging from 6 x 1/2 through to 8 x 1-1/4, covering the most commonly specified dimensions for sheet fixing work. Buying by the box keeps the cost per screw sensible and means you are not rationing fasteners when the job runs long.