Review on Efficient Doweling Centering Woodworking Accessories for Precise Transfers by Chad Cypert

So I ordered a pack of 20 and apparently the person who placed the order couldn't tell the correct sizes either because instead of 3/8 got about 10 mm. It's just big enough that you either have to drill a hole or spend a lot of time trying to get it out. The seller has communicated with me and it appears these are metric sizes which are "close enough" to imperial equivalents.