43 material Nickel Zinc suitable for wideband transformers up to 50MHz, and suppression of EMI from 3 to 250MHz bands ui=800.  43 material is also ideal for suppression of switching noise from switch mode power supplies by winding the mains power cable through a larger toroidal core multiple times.  These are also recommended for use on HDMI cables from computer video cards to suppress noise in the 3 to 20MHz bands.  Commonly used for construction of 3 to 30MHz Antenna Baluns and 1:1common mode RF chokes.  Refer to the 43 Material Data Sheet for more information.