We used to cut out of social studies to hang in metal shop, so of course we love these Bellota professional-grade cutting discs. You will, too, if you’re into cutting metal, which is what these beasts were born to do. Both have 7/8” hubs. You pick: the 5” dia x 9/32” thick disc with a max rpm of 12,200; or the 7” x 1/16” thick disc with a max rpm of 8600 (part number 50320-180, which we think is also the grit of the cutter).