Electropolishing is used for polishing of metal parts. The principle is just the reverse of that of electroplating. The workpiece is made the anode in an electrolyte, with a cathode added to complete the electrical circuit. In the resulting deplating, material is removed most rapidly from raised, rough spots, producing a very smooth, polished surface. This process is primarily used for obtaining mirror-like surfaces from highly smooth initial surfaces. A final finish of less than 0.05 m can be obtained if the initial surface roughness (root mean square) does not exceed 0.18 to 0.20 m. Electropolishing is used for polishing stainless steel sheets and parts.