The Magafor 4835 series cobalt steel single-end countersink with a TiN coating creates a 100-degree conical opening that accepts a rivet so it sits flush with the surface. Cobalt steel provides extended tool life compared to high-speed steel when cutting hard materials, and maintains the tool's toughness and hardness in high drilling temperatures. The titanium nitride (TiN) coating offers increased hardness for better wear resistance and a longer tool life than an uncoated countersink. The tool has a single cutting end and a round shank that accommodates most drill chucks.

Countersinks are fluted cutting tools that cut a conical or gradually widened opening for a hole into the surface of a workpiece, which provides a seat for a screw or rivet head. They are also used to create center holes for a machine center, deburr surfaces, and enlarging existing holes. The countersink's body diameter should be the same size or larger than what is being countersunk.

Magafor manufactures precision cutting tools, including counterbores, countersinks, deburring tools, and end mills. The company, founded in 1937, is headquartered in Fontenay-sous-Bois, France.