The 12mm countersink bit is a cutting tool designed to create a 12 mm diameter conical recess so that countersunk screw heads sit flush with or below the workpiece surface, and to deburr holes after drilling. Its primary use is to prepare holes for flat‑head screws and to remove sharp edges in wood, plastics and light metals during assembly and finishing operations.

This Draper Tools Group D countersink is manufactured from M2 high speed steel (HSS M2) with a precision‑ground cutting face to retain sharpness under sustained use. The tool is supplied in a bright ground finish, and variants with TiN (titanium nitride) coating are commonly available for increased wear and corrosion resistance. The cutter presents a 90° conical angle, matching the geometry of most countersunk fasteners and conforming to common ISO/DIN recommendations for countersink geometry. The shank is suitable for standard drill chucks; 1/4in hex shank variants are available for use with quick‑change hex chucks on impact drivers and cordless drills.

Typical applications include carpentry and joinery, cabinet making, plumbing and electrical installation where neat screw seating is required, plus light fabrication and sheet‑metal work for deburring and chamfering holes prior to assembly. The HSS construction allows clean cutting in soft steels, aluminium and non‑ferrous alloys as well as wood and plastics, making it a versatile tool for contractors, maintenance engineers and workshop technicians.

Key benefits include the durable cutting edge and heat resistance of HSS M2, optional TiN coating for extended tool life and improved corrosion resistance, and compatibility with common drill chucks and quick‑change hex systems. The 90° angle ensures reliable seating of standard flat head screws and produces consistent, centred countersinks when used with pilot drills or drill press guides.

Duchy Fasteners stocks the 12mm countersink bit in single units and multi‑packs, with shank options (round and 1/4in hex) and both bright and TiN‑coated finishes available across a range of pack sizes to suit trade and workshop requirements.