SU Coils KEMET SU Coils are low current type AC line filters that are offered in a wide variety of sizes and specifications. These gear-type coils are designed with proprietary ferrite cores and are useful in various noise countermeasure fields. KEMET SU Coils are UU-assembled with small-size core dimensions and small current (200mA to 4A). These coils are available in vertical and horizontal assemblies. Typical applications include audio-visual equipment, office automation equipment, digital appliances, and power supply devices.