Professional polishing stones for commercial or occasional use Suitable for wide range of uses including grinding, polishing and carving All of the stones come with a 1/4" / 6mm or a 1/8" shank so will fit any drill or die grinder with a 1/4" or 1/8" collet Total length of the shaft is 1" long The shaft is manufactured from chrome vanadium steel for strength and durability This kit contains 10 stones In the kit there is a total of 10 different shapes of stones for all different requirements and needs Aluminium oxide material