The plots here show attenuation (Insertion Loss) for different options in the series from 10 kHz to 30 MHz. The Example here is a 2 A model where the engineer can compare between FN9280, FN9280B, FN9280EB, FN9280E, FN9290 and FN9290B. Refer to datasheets for other current ratings. Curve A indicates symmetrical (differential mode) attenuation while curve B indicates asymmetrical (common mode) attenuation in a 50 ohm measurement setup.