Dart Premium torsion SQUARE impact driver bits.
Square (Robertson) heads are most commonly associated to Pocket Hole Screws and Decking Screws.

High quality impact resistant driver bits ideal for use in the most demanding applications with a standard 1/4” hexagon fit. 
Tough, torsion absorbing bits which have been designed especially for use with impact drivers.
Magnesium Phosphate coated for excellent wear resistance.
Available in 2 length options:
25mm for use with an impact ready magnetic bit holder (DIMBH-1)
50mm for direct fit into impact drivers as well as magnetic bit holders* 
Trade packs of 10 bits of one size.
*Magnet only -  not any which feature a spring clip holding inside the hex