Cap screws or hex socket screws and bolts are fairly vulnerable to rounding out, partiularly stainless fasteners. Countersunk hex sockets screws and button heads are an absolute nightmare if they're over tightened, because the hex socket is fairly small compared with the screw diameter. When we were offered this product to test we were fairly sceptical, but we would not let the rep have back the sample once we had tried it! For a tool set that only costs a small round of drinks, it is amazing.

The standard 1/4" bit drivers cover 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm heads.

The 7mm, 8mm and 10mm use a 10mm hex driver and there is a 1/2"drive to 10mm bit holder included in this comprehensive set.