8G x 13 mm Countersunk Undercut Square Drive Self-Tapping Screw - CUSA28GX13

The CSK Undercut Self Tapping Screw Square Drive, A2 (304) Stainless Steel is available in 4 sizes (8G to 10G) and is a countersunk head screw with an undercut head and a square drive recess. It is a self-tapping type used for fixing into thin metal, plastics and timber.

A2 (304) stainless steel is the common general-purpose austenitic grade. It resists corrosion well indoors, in fresh water and in most general outdoor conditions, but it is not recommended where chlorides are present, such as coastal, pool and marine settings. Choose A4 (316) there. Gauge sizes are shown as a number followed by G. On this range 6G is 3.5 mm, 8G is 4.2 mm, 10G is 4.8 mm, 12G is 5.5 mm and 14G is 6.3 mm, as listed by the supplier.

The range runs to 4 variants, covering sizes 8G to 10G and lengths 13 mm to 19 mm. Variants are supplied in packs of 500 to 1000, depending on size.

In wet conditions, keep stainless steel apart from aluminium and galvanised steel with a washer or sleeve, to reduce the risk of galvanic corrosion.

Where this product is used

• Flush fixings in sheet metal and timber
• Trim and panel fixing
• Signs, furniture and fittings
• Bulk jobs and trade or maintenance stores buying in larger packs
• General workshop and maintenance use
• Indoor architectural and joinery work

Features

• Square recess reduces driver slip
• Choice of 4 sizes, 8G to 10G
• Supplied in packs of 500 to 1000
• Countersunk head with an undercut under the head
• A2 (304) stainless steel for indoor, fresh water and general outdoor use
• Lengths from 13 mm to 19 mm

Key specifications

Selecting the right option

Sizes are shown as gauge (G) with the nominal diameter in mm where the supplier lists it. Use a square drive bit that matches the recess, drill a pilot hole and keep the driving speed low.