IEY1668 Features: * High speed steel step drill bits allow for drilling multiple hole sizes with one bit * Specially designed to automatically debur holes as it drills * A balanced double flute design minimizes chattering * Does not require pilot bit * 1/4"" shank diameter * 13 hole sizes * 1/8"" through 1/2"" in 1/32"" increments * 1/8"" step depth * 1/4"" shank diameter * Carded