Neo Disc - D3mm x 1.5mm Magnet. Magnetic Product Description: This rare earth disc has a diameter of 3mm and a height of 1.5mm. It has a magnetic flux reading of 4455 Gauss and a pull force of 160 grams. It is identified by the AMF magnet part number 20090. Uses for our rare earth disc magnets: Metal separation, picking up nails & screws, water conditioning, building generators, magnetic stirrers, metal detectors, tool knife holders, holding, stud finders, magnetic therapy, magic tricks, brochure closures.