Magdev sintered neodymium iron boron n35h permanent block magnets magdev blni00680 n a 20 x 10 x 5mm permanent block magnet made from n35h grade sintered neodymium iron boron ndfeb this type of magnet material gives the highest energy per unit volume of any permanent magnet material being capable of lifting up to 1000 times its own weight suitable applications for this disc magnet include audio aerospace automotive medical and renewable energy magdev blni00680 n neodymium iron boron 2