Drill bit shank The name comes from the German "Stecken – Drehen – Sichern" (Insert – Twist – Secure). In German-speaking countries the back-formation "Spannen durch System" (Clamping System) is used, though Bosch uses "Special Direct System" for international purposes. The triangle shank is almost always made by machining three flats on round bar stock. It is intended as a minor modification of a straight shank, still allowing it to be held in a 3-jaw drill chuck, but allowing higher torque transmission and limited slipping. The Morse taper twist drill bits pictured right are used in metalworking. The full range of tapers is
Drill bit itself handles the point deformity, as it is a low-wear task. The bit is hardened and coated against wear far more than the average drill bit, as the shank is non-consumable. Almost all indexable drill bits have multiple coolant channels for prolonged tool life under heavy usage. They are also readily available in odd configurations, such as straight flute, fast spiral, multiflute, and a variety of cutting face geometries. Typically indexable drill bits are used in holes that are no deeper than about 5 times the bit diameter. They are capable of quite high axial loads and cut very fast.