Side hole on drill bit cylinder cover supports fast remove of sawdust with no jam The Superior Parts 19149 Big Horn's 5mm Vix Self-Centering Hinge Bit is an essential tool designed for precision drilling. This bit is particularly... Big Horn 19149 5mm #10 Hex Shank Hinge Bit fits size #10., Self-centering & accurate. Tork Craft Drill Bit Hss Standard 1.5Mm Hex Shank 1/Card - Northern Self Centering Hinge Bit Genius Tools [2149] 9mm Hex Shank, 9mm Hex Screwdriver Bit 30mmL 9mm Hex Shank, 9mm Hex Spring Loaded Pilot Hole Bit Self-centering function of drill bit for precise positioning and drilling without walking around , 1/4 hex shank (6., 35mm), fast, one-handed load and release of bits Big Horn 19144 #14 Hex Shank Hinge Bit The spring loaded outer guide keeps drill centered for perfect pilot holes. Bodies are stamped with size.