This is the stock grinding wheel that comes with the T&S CZ223 Square Chisel Grinder, and the CS118 3/8" & 404H. It has a medium hardness and grit. It has an 8" outside diameter, with a 1" diameter for mounting, and is 3/16 thick This stone will fit Simington, Silvey, & other pond and deck grinders with a 1" mounting arbor.