Irwin Wood Countersinks #4 x 7/64"

Tapered drill with widened flutes for drilling fast, clean pilot holes.
Adjustable four-cutter counterbore cuts and clears chips quicker for fast, smooth countersinking.
Counterbore attaches to flats on shank with two hex screws for a secure fit, and can be adjusted for controlled pilot hole depth.
1/4" quick-change shank reduces slipping in standard chucks and is compatible with all 1/4" quick-change chucks, including impact drills.