The BrushAll 4.5" Diamond Cut-Off and Grinding Wheel, No. 8152, from Innovative Products of America, features a core bonding technology that adheres a medium-grit diamond to the steel core of a Type-27 depressed-center wheel, which helps the wheel maintain its size and shape while lasting 60 times longer than standard abrasives, according to the company. The wheel offers a diamond abrasive coating on three surface areas and can be used for surface-prep grinding, but it is still thin enough to be used as a cut-off wheel. It includes a thin-profile nut for use with standard angle grinders with 5/8" x 11 threads.