Set of 20 Dormer High Speed Twist Drill Bits Made of the highest quality steel, carefully tapered and ground to size. All drill bits have straight shanks and are perfectly finished to assure quick, smooth and clean drilling. Set contains sizes 61 (0.99mm) to 80 (0.34mm). Comes in a selector case with slide cover, to access only the size you need. Sizes are noted right on the case. Drill bits can be easily replaced, so the set is always in order and protected.