SC & SCF-X Coils KEMET SC and SCF-X Coils are standard-type AC line filters that are available in a wide variety of sizes and specifications. These toroidal coils are designed with proprietary ferrite cores and are useful in various noise countermeasure fields. Typical applications include audio-visual equipment, office automation equipment, industrial equipment, digital appliances, and power supply devices. KEMET provides a three-phase SCF-X coil series with ultra-high inductance, ultra-high permeability, and toroidal coils with nanocrystalline metal cores.