DRILLCO DRL1312A137 - 37/64Extra Length Drill 12"" OAL"Brand Drillco Product SKU 1312A137 Category Drills Size Fractional Material High Speed Steel Finish Coating Black Oxide Pack Quantity 1 Size 37 64 Overall Length 12 Flute Length 9 Description Because of the inaccessibility or the extreme depth of a hole it is found that even long series drills are not long enough. The drilling of such holes generally requires the use of an Extra Length Drill. The drills are made with a general purpose flute design