The BlueSpot 10 Piece Mounted Stone Set is ideal for grinding, polishing, carving and cleaning. Features bonded aluminium oxide construction for increased durability.Package Contents - 6mm / 1/4" mounted stone (x5). 3mm / 1/8" mounted stone (x5).Ideal for grinding, polishing, carving and cleaningBonded aluminium oxide construction for increased durability3mm & 6mm shankGrey coloured mounted stones are manufactured from brown corundum and are suitable for use on cast ironPink coloured mounted stones are manufactured from chrome corundum and are suitable for use as a grinding tool