Our bandpass filters are an important multi-radio station  upgrade for contesters, Field Day Operators, and when two or more radios and antennas want to operate in very close proximity together. C3 Electronics LLC HF Band-Pass Filters  help you achieve exceptional operations by reducing unwanted signal interference while operating amateur radios. These filters are exceptional help in ARES communications trailers and campers with multiple operators.  C3 Electronics LLC filters come with a One-Year Repair or Replacement Warranty and are manufactured in Wisconsin.