Eriez says its powerful magnetic pulleys provide automatic removal of unwanted iron from materials on conveyor belts, which prevents machinery damage and product contamination. The self-cleaning units, offered in permanent and electromagnetic designs, are available in 80 combinations of diameters from 8 to 36 inches and in belt widths from 8 to 60 inches. The Permanent Magnet Axial Interpole Pulleys are constructed of quality steel center tubes with welded dividers to securely hold magnet stacks. They are finish painted, and hub bore holes are coated to prevent rust or pitting.