FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz, Case of 100
case if 100 ferrite ring cores - Very useful for AC/DC power, coax cable common mode current suppression. For highest choking resistance, wrap cable through center of ring as many turns as possible. DO NOT use for impedance transformers (2:1, 4:1, 9:1, etc.) - use Mix 43 or Mix 61 for high power.