This is a set of crowns and titanium crowns. Titanium bits have a hex shank and range in diameter from 1/16" to ΒΌ". They are supplied on a plastic stand with diameter markings. There is diamond dust at the tips of the crowns. They are packed in a zippered bag. My husband tried the titanium bits that came with this set and found them quite dangerous for not being centered on the shank. They vibrate at a great and increasing frequency as he tries to drill them on his drill. He refused to try hole saw drills due to problems with titanium crowns. In general, this product is dangerous and should be avoided.