letter sizes. Their HSS keeps the bits sharp for my uses (wood, aluminum brass, and, less often, steel). For those with more extensive use, Triumph has an extensive selection of other even more enduring, bits, but I've never needed anything except their HSS in bright or black oxide finish. You can find cheaper bits, but they are unlikely to be the uniform high quality that Triumph supplies. For tools, I strongly recommend USA or Canada manufacturers. Triumph manufactures in the USA.

Note, this geometry is less than ideal for brittle plastics, such as acrylic (Plexiglass). For these materials, I keep a set of 155 degree split point bits.

Triumph products can be seen at /triumphtwistdrill.com/. I'm delighted that Carbide Processors carries this find manufacturer.

(I have no connection to Triumph Twist Drill or its parent company, Minnesota Twist Drill.) Read LessRead less about Triumph makes quality drill bits. This