Irwin Impact Tapcon Installation Drill/Dri *Sub Brand: Tapcon *Drill Size: 3/16 in. *Material: Cobalt Steel *Product Type: Impact Drill Bit Set *Number in Package: 4 pc. *Shank Type: Quick-Change Hex Shank *Usage: For Drilling in Concrete *Packaging Type: Carded *Shank Diameter: 1/4 in. *Includes: 5/16" nut driver, #3 Phillips bit and 2" power bit.