1. Size: 40nm, purity: 99.9% 2. Magnetic recording materials 3. Magnetofluid 4. Absorbing materials 5. Magnetic slurry Application of iron nanopowder:magnetic recording materials2. Magnetofluid: used in sealing and shock absorption, medical apparatus and instruments, sound controlled, lightshow, etc.3. Absorbing materials4. Magnetic slurry5. Nano oriented agent