Drill bit shank A hex shank can be grasped by a 3-jaw drill chuck or held in a chuck specifically for hex shanks. Quarter-inch hex shanks are common for machine screwdriver bits and have spread from that application to be used for drill bits that are compatible with screwdriver machinery. The diameter of an SDS and SDS Plus shank is 10 millimeters. (The SDS Max is 18 millimeters.) The SDS shank has the advantage of fitting into a simple spring-loaded chuck, so that bits are simply pushed into the chuck without tightening. This shank and chucks made for it are especially suited to
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,