2" Dia. Mounted Strong Ceramic Ring Magnet PKG (4) This ceramic ring magnet with a 13/16" ID is glued into a 2" dia x 3/8" thick plated-steel bracket, which adds to the strength of the magnet. There's a broken-off rivet in the center, leaving a little hole that you could put a string through if you do that sort of thing. Magnet has a 10-lb pull.