Imperial Pozi Countersunk Screws.

What are Imperial Pozi Countersunk Screws?

Imperial Pozi countersunk screws are precision screws designed for flush-fitting installations where an imperial thread size and Pozi drive are required. 

Featuring a countersunk head profile and cross-style Pozi drive, they are commonly used in mechanical assemblies, enclosure, and panels across aerospace, electronics and general engineering sectors. 

How Imperial Pozi Countersunk Screws Work

Designed with a Pozi drive recess for improved torque transfer and reduced cam-out, these screws offer more reliable engagement than traditional Phillips heads. The countersunk profile ensures the screw head is embedded into the component surface, which is ideal when a smooth, snag-free finish is essential. These screws thread directly into pre-tapped holes or pair with matching imperial nuts, ensuring compatibility with standardised imperial systems.

Materials Imperial Pozi Countersunk Screws Are Made From

Accu’s range of imperial Pozi countersunk screws is available in the following materials and finishes:

• Steel (Grade 4.8): A versatile, cost-effective material offering good tensile strength for general fastening applications.
• Bright Zinc Plating: Provides corrosion resistance and a clean metallic finish, ideal for indoor or dry environments.
• Black Oxide Finish: Offers minimal corrosion protection with a sleek matte appearance, often used for aesthetic or low-visibility installations.

Sizes and Types of Imperial Pozi Countersunk Screws Available

Our selection includes a variety of thread sizes and lengths to meet a variety of imperial specification needs:

• Thread Sizes: From 2-56 UNC to 1/4-20 UNC
• Lengths: 1/4" to 1"
• Pozi Drive Sizes: PZ1 and PZ2
• Head Style: Countersunk

These specifications support accurate replacement in legacy systems or compatibility with imperial-threaded components.

FAQs

Q: What is the difference between imperial and metric Pozi screws?

A: Imperial Pozi screws follow inch-based thread dimensions like 4-40 or 1/4-20 UNC, whereas metric variants use millimetre-based threads (e.g. M3 or M6). Imperial sizes are often preferred in legacy systems or industries like aerospace and defence.

Q: Can I use an imperial Pozi screw in a metric tapped hole?

A: No. Imperial screws have different thread pitches and diameters than metric screws. They’re incompatible and using the wrong type can damage components.

Q: What tools are compatible with Pozi screws?

A: Pozi screws require a matching Pozi screwdriver or bit (typically marked PZ1 or PZ2). They differ from Phillips heads and should not be used interchangeably for best performance.

Bespoke Imperial Pozi Countersunk Screws Manufacture.

High precision, bespoke manufacture of Imperial Pozi Countersunk Screws to customer specification. State of the art facilities specialising in both small batch prototyping and large scale manufacture.