Round Disc Magnet Shape, Machined Silver Steel Finish. Durable Lasting Shine, Perfect for Refrigerator Magnets, Office Magnets, Whiteboard Magnet &Dry Erase Board Magnet Say Goodbye to scratches and clutter as they are past and hello to your new tabletops Robust, long-lasting, stainless steel, corrosion resistant Magnets made from Brushed Nickle silver satin material. They Are Ferrite Magnets, not strong magnets, Grade 5.They are highly stability under difficultly environment.