If you want precision drilling/driving in a wide range of material including wood steel aluminium and more this 20 piece drill and driver bit set is ideal. Manufactured to the highest quality the drill bits in the set are Titanium coated for durabilit- A useful 20 piece drill and driver set- 1/4in (6.35mm) quick change chuck- Hex shank drill bits - mm : 2x 1.5 2 x 2.5 3 4 5 6- 50mm long screwdriver bits : Slotted: 5mm & 6mm Philips: PH1 2 x PH2 PH3PTDCLA1801760