The C114COMBC comprehensive set of 114 NAS907 type J jobber drill bits, in a metal chest for safety and security, consists of: R10CO sizes 1/16? to 1/2" in 1/64? increments, R18CO in sizes from 60 to 1; and finally 2ACO sizes 1 mm to 13 mm in 0.50 mm increments. All of the drills in the set come with a 135 degree split point, for easy location and rounder holes, and reduces the push force needed, whilst the bronze oxide finish prevents workpiece material from sticking to the cutting edges of the tool so you get clean and accurate results. The drills are manufactured from premium High Speed cobalt and are suitable for drilling hard materials including tool steel, with a heavy duty design, recommended for use in difficult materials and applications.