This part of ISO 603 specifies the nominal dimensions, in millimeters, of: — Type 41: Flat cutting-off wheel — Type 42: Depressed centre cutting-off wheel These bonded abrasive products are intended to be used for cutting-off or slotting of any part of a workpiece. The workpiece is firmly clamped or is stabilized by its own weight. If the cutting-off wheel is guided by hand the workpiece is fixed and vice versa. The cutting-off machine is fixed during the operation.