Pro Drywall Screw Adapter for Screw Gun Drill Impact Driver Get professional results attaching drywall sheets to stud walls Unique bit has #1 Phillips with permanent 9/16"-dia. collar that prevents over-driving screws Takes screw-head flush with drywall surface, prevents pressure bumps and divots Lets you work faster with more-consistent results; reduces filling/sanding time & effort 1/4" hex shaft fits all drill chucks, driver collets; works great with magnetic bit holders