Used to countersink and counterbore for the heads of screws in woods, plastics, and non-ferrous materials. Made of Carbon Steel and heat-treated for long tool life. The Type C countersink is designed for use in all woods, plastics, and non- ferrous metals. The countersink is held in place with 2 hex socket set screws fastened into the flutes of the drill. This countersink can be mounted on taper point, brad point and regular point drills. These countersinks will be well used in your woodshop. Don't buy those cheap countersinks. Legend below explains sizing. Select your item(s) then click Add to Cart. Legend (in inches unless otherwise noted): CD = Cutting Diameter DHD = Drill Hole Diameter OL = Overall Length Technical Info W.L. Fuller Inc. is a family owned, third generation, manufacturer of the best countersinks, counterbores, plug cutters, taper point drills, brad-point drills, and step drills. They have over 60 years of experience in manufacturing tools to cut woods, plastics, and metals.