DEWALT DT7390T-QZ 
PZ1 X 50MM IMPACT TORSION BITS (5)
The 15 degree torsion zone allows the screw driver bit to flex rather than breaking.
The Full Fit head prevents the rounding of the screw head and prevents ‘cam out‘ (bit head slipping out of screw head due to the turning force).
The Magnetic Screwlock enables tasks to be completed quicker and easier, reducing instances of dropped or lost screws.