4 Piece, Premium Percussion Masonry Drill Bit Set, Flute Design Efficiently Removes Dust Reducing Bit Binding, Optimum Grade Of Carbide Maximizes Durability, Carbide Tip Provides Up To 2 Times Longer Life, Tip Configuration Reduces Walking For Improved Accuracy, Contains 3/16" x 3, 1/4" x 4, 5/16 "x 6, 3/8" x 6.