The flutes are ground behind the lands to funnel chips to the inside of the bit and away from the outside diameter
IRWIN Multi-Material drill bits drill through just about any type of material out there – brick
rimless design provides all day user comfortAdjustable length temples provide a secure
Fits all SDS-plus and Hilti TE-C rotary hammersReduced area above the flute prevents the drill bit from binding while drilling-the full usable length can be utilizedChrome vanadium shaft through-hardened to 50-53HrCPatented tip and flute design removes dust more efficiently - up to 25% faster than other bitsShot-peened
Extra Long For Added Strength
Aircraft Black Oxide Drill Bit, 12 x 5/16-In. Power Equipment The flutes are ground behind12" x 5 16", aircraft, black oxide, drill bit, 135 degree bit perfect to use in hard to reach areas & to run wires & cable, has split points & has a surface treated high speed steel for wear resistance.