Yes. It's for a 7/16" tube for curved bridges. I have a round carbide insert tool that is just slightly smaller than 7/16" so I had to sort go in from the right, then the left and then back to the right and then compare to the tube and make further cuts from there. It wasn't too bad. I happened to have picked up a few 2"-3" rounds that were nearly perfectly .500" thick with 1/2'' hole. The handle part needs some work. The follower slips and doesn't follow the curve well which causes the tube to kink.
__________________
https://www.flickr.com/photos/54319503@N05/
http://www.draper-cycles.com