Need to know what drill bit to use to tap a hole for a screw or bolt? Or maybe you just want to drill a thru hole for one.TapDrillTool makes it REALLY easy to find out. No tables to scroll through, no screw selection pages - just dial in the screw size, pitch and desired engagement percentage and your options are displayed instantly. You'll see the optimal hole size and the bits that come closest to your request, along with the resulting engagements and hole size errors.Features include:- Inch screws from #000 thru 1-7/8"- Metric screws from M1 thru M56- Thread engagement from 50% thru 80% or Thru Hole (Body Drill)- Works for both cutting (most common) and forming taps.- Results for Letter, Number and Fractional drill bits.Press the Thread Type button to select another type.NOTE: Unless I am mistaken about what the reviewer was asking for (and, by the way, I _really_ appreciate him having taken the time to rate and review the app) TapDrillTool _does_ provide a Body Drill size: just set the "Thread Engagement %" spinner to "Thru Hole".** Just want to know how to drill for a part you've measured? Check out CaliperTool elsewhere in the App Store.