Ideal for drilling holes to be tapped & other precision jobs. 60 Bits/ M2 HSS high speed steel. Hardened & tempered. Precision roll forged. Surface treated features abrasion resistance & chip ejection. Number sizes from #1 to #60 (0.228"-0.040" or 5.79mm-1.02mm) Straight shank. Includes heavy duty metal index box. Please note the metal case color is black