Magnetic Grate Separators, sometimes called "hopper magnets", deliver ferrous tramp metal separation in bins, chutes, drawers, hoppers and circular enclosures. Industrial Magnetics Drawer Magnets or Drawer-In-Housings consist of a row, or most commonly, rows of round magnetic tubes that are assembled into drawers. Each drawer magnets' tubes are aligned on alternating centers from the row directly above or below it.