Resharpen Dull Drill Bits - The 250 Handyman drill bit sharpener is ideal for most types of twist drill bits and masonry bits from 3/32in. to 1/2in. (2.5mm to 13mm) diameter in about 60 seconds. Sharpens high speed steel, carbide, tin coat, cobalt and masonry bits 118 degrees with the replaceable diamond grinding wheel for sharp, precise results. One year manufacturer's warranty. Made in the USA.