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.
Bit (key) Bit (key) The bit of a key is the part that actually engages the locking mechanism of a lock. (For example the tumblers in a pin tumbler lock.) The exact geometry of modern keys is usually described by a code system. This is referred to as the bitting. The bitting instructs a locksmith how to cut a certain key, to replace a lost key or make an additional copy. The bitting is usually a series of integers (e.g. 372164) that is usually translated from a key code chart or from a bitting code list to settings on specially designed key