[Material]: These flute countersink drill bit sets are machined from high-speed steels and are available in 6 different diameter sizes.

[Size]: 6mm(1/4''), 8mm(5/16''), 9mm(3/8''), 12mm(1/2''), 16mm(5/8''), 19mm(3/4'').

[Eliminates Chatter&Vibration]: All have a 90° angle on the point for sharp and precise countersinking. The cutting edge is hardened and honed for sharpness. A Chatter-Free,five-flute design with staggered cutting teeth arranged to insure free chip flow and rapid chatter-free cutting.

[Mutiple Application]: Ideal for wooden planks, fiberboard, particle board, plywood, plastic, aluminum board, PCB board, and more Premium Design - Great for Sinking 90 Degree Holes into Wood and Soft Metals Countersunk Screws and Fixings.Suitable for DIY, Home, and General Building/Engineering Using.

[Use]: 1/4″ hex shank countersinks are fine for a quick drill. They don't slip in drill chucks. You can make deep countersinks easily by setting the countersink's depth stop to allow the countersink to drill more deeply into the work surface. Be sure to measure the size of your plug to be sure your countersink's body will make the right-size hole.