Draper 1x No 4 Cross Slot Impact Screwdriver Bit Professional Tool 10820. This screwdriver bit features a No 4 Cross Slot design and an 8mm hexagon shank, making it suitable for use with Stock Nos. 22322 and 81519 Impact Screwdriver Sets. It is sold loose. PZ TYPE bits are compatible with Pozidriv/Supadriv fixing systems. Draper TX-STAR products are compatible with Torx fixing systems. Specifications: Type: Impact Driver Bit, Drive Type: 1/4" Hex, Head Size: PH4, Head Type: Phillips, Number of Pieces: 1, Overall Length: 25mm. Dimensions: 3.50cm x 0.80cm x 0.80cm. Weight: 0.01kg.