I took the micrometer out and as many other reviewers have said they aren't even close to that size. They MUST be 0.3mm to 1.0mm in 0.05mm increments. Then increase by 1.0mm in 0.1mm increments to 1.6mm. This is advertised. Reality? Not even close. The smallest bit was 0.59mm and I had three of them. The largest was only 1.4mm and I had two of them. Basically, it's junk thrown into a clever suitcase under terrible quality control. If you only want to drill small holes and don't want a specific size, then this is for you. If you're looking for carb nozzle sizes or anything else you need precision with, skip them.