Review on Sunjoyco 4-Inch Diamond Cup Grinding Wheel - 12-Segment Heavy Duty Turbo Row Disc For Concrete, Granite, Stone, Marble, Masonry And More by Phillip Johnson

I was a little apprehensive since the cost was somewhat low but decided to try it, needed to grind some grout between flagstone patio pavers. This little wheel work like a champ, did everything I needed it to do and then some with little wear and tear on the wheel itself. It comes with an insert and my grinder has a padded wheel hub so the insert wouldn't stay in place but once I turned the hub over to the solid metal side, the grinding wheel and insert stayed firmly in place with no issues.