Jantzen Audio Iron Core Coils are made of high purity copper around a Permite core for high inductance while remaining very economical. The extremely low DC resistance value does not affect the damping factor and efficiency loss. The Permite material provides a lower delay than Ferrite core coils while offering higher power than Ferrite core coils. This type of coil is generally very popular for setting up the bass and midrange crossover. The power handling is determined by the size of the core and the thickness of the copper wire. The thicker the core size and the wire, the higher the power handling.