These are excellent bits, and I prefer the fine pivot drills when the drill size is less than 1mm. In this case, the drill is 0.5mm, but the shank is 1mm - gives your pin vise something to grab onto and makes them easier to handle. I have bought a number of these in different sizes, from 0.3mm to 0.8mm, and am happy with all of them. Could apply this same review to all of them.