Professional tool for commercial or occasional use. Manufactured from heat treated steel for strength and durability Single twist design efficiently ejects chips for cleaner holes. Each piece can drill and countersink in one go. Suitable for steel (thin materials) as well as a variety of other materials (wood or plastic etc...) Adjustable for the depth of the hole required. 7 Tapered drill bits 7 x countersinks 7 x adjustable step collars 1 x Hex key set for easy and quick adjustment when required. Comes in a plastic blow molded case for easy storage and transportation. Set Includes; Sizes: 1/8" / 9/64" / 5/32" / 11/64" / 3/16" / 13/64" / 7/32"