found these in one of dads toolboxes. all inside edges are sharp, knurling present on solid end. marked 1/16 to 3/4 in 1/16 increments.
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Saw my Dad use those lots of times.Here is Harbor Freight's version.
https://www.harborfreight.com/9-piece-hollow-punch-set-3838.html
Good set to have around if you ever need to make a gasket.