Irwin Speedbor 8-Piece Spade Bit SetBlue Groove point and cutting edge for faster chip removal. Double cutting spurs scribe the outside of the hole reducing breakout. 10% larger shank for added durability. Grooved hex shank prevents slipping in drill chuck or bit extension. Includes Pro Set case made of molded ABS resin with full length metal hinge pin. Bit identification is simple with easy to read size markings. 6' shank length, 1 4' shank size. Set includes: 3 8', 1 2', 5 8', 3 4', 7