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Drill Hog® #31 Drill Bit #31 Number Bit Molybdenum M7 Lifetime Warranty 12 Pack | eBay
Drill America 31/32 in. High Speed Steel Twist Black Oxide Reduced Shank Drill Bit with 3/4 in. Shank RSD34X31/32 - The Home Depot
CLE-LINE, #31 Drill Bit Size, 1-5/8 in Flute Lg, Jobber Length Drill Bit - 22N372|C18084 - Grainger
Century Drill & Tool® 26231 - Pro Grade™ 31/64" Cobalt SAE Straight Shank Right Hand Drill Bits (3 Pieces) - TOOLSiD.com