31 Wire Gauge Drill Bits Jobber Length Numbered Drill bit. Wholesale Bulk Drills. Drill Bits made of High Speed Steel are for sale by Bisco of Florida. 31 Numbered Drill Bits in Wire Gauge Sizes have a .1200 Decimal Equivalent, 1-5/8" Flute Length, and 2-3/4" Overall Length. These wholesale number drill bits are designed for drilling a broad range of materials in the steel and iron families. Wholesale Numbered Drill Bits are surface treated with abrasion-resistant black oxide.