【Premium Large Sizes Set】8 pack of 6" long reduced shank drill bits (9/16”, 5/8”, 11/16”, 3/4”, 13/16”, 7/8”, 15/16”, 1”) stored in a aluminum case. 【Premium Material and Coating】Industrial grade M2 cobalt high speed steel construction for proven capability and durability. Gold titanium and black nitride coating more durable and corrosion resistant than regular. 【Efficient 135° Tip Design】Fast penetrate hard materials, reduce clogging, improves wear resistance, ensuring efficient drilling performance. 【Universal 3-Flat 1/2" Shank】The 1/2 Inch reduced shank is compatible with all drill presses and most power tools. 【Wide Application】Perfect for drilling steel, copper, aluminum, brass, wood, MDF, PVC, acrylic, nylon and composite materials.