Drill bit shank shaft and shank, is usually of the same diameter. It is held usually in a three-jaw drill chuck. Bits of diameter too small to grip firmly can have straight shanks of larger diameter than the drill, which can be held firmly in a standard size collet or chuck. Large drill bits can have straight shanks narrower than the drill diameter so that they can be fitted in chucks not able to chuck the full diameter. Such a drill bit is called a reduced-shank or blacksmith's drill. For example, this allows a bit to be used in a pistol-grip drill's chuck.
Drill bit metric and imperial sized drill bits alongside the required screw tap sizes. There are also certain specialized drill bits that can create holes with a non-circular cross-section. While the term "drill" may refer to either a drilling machine or a drill bit for use in a drilling machine, in this article, for clarity, "drill bit" or "bit" is used throughout to refer to a bit for use in a drilling machine, and "drill" refers always to a drilling machine. Drill bit geometry has several characteristics: Most drill bits for consumer use have straight shanks. For heavy duty drilling in industry,