The magnetic plate for polishing process are used in the industry to hold pieces during the polishing processes. The upperside contains permanent magnets and the underside has steel brackets to adjust the height of the plate by means of screws. It is not demagnetitzable.
Simple operation: they are usually placed under the conveyor with the magnetic face touching the belt and its function is to hold the pieces during polishing. When the pieces pass over the belt, they are retained by the force of the magnetic plate, avoiding to be shot out while polished.