Coilcraft makes many EMI/RFI filters including surface mount and leaded components, LC filters, and signal line filters, which work on RJ-45, RJ-15, and RJ-11 lines. Their LC filters include high and low pass models and feature less than 0.3 dB insertion loss with 50 or 75 Ohm characteristic impedance.

Coilws.com makes several EMI/RFI filters including leaded filters, LC filters, and surface mount components. Their low power Line Filters for video signals have a current rating of 700 to 500 mA with inductace of 10 to 80 uH, while their high power common mode Line Filters come in horizontal or vertical mount models with current ratings of 0.38 to 6.0 amps AC and inductance of 1 to 120 mH.

Filtronetics makes custom EMI/RFI noise filters such as bandpass, high pass, bandstop, and lowpass filters, with frequencies of >1MHz to 6GHz. They also have LC filters, diplexers, surface mount models, and ISM filters. Some applications include military and microwave filtering.

KR Electronics makes custom and standard filters for commercial and military uses including Low Pass filters, high pass filters, band pass filters, LC filters, Diplexers, and surface mount filters. Their low-pass filters have a cutoff frequency of 5 HZ to 500MHz, while their bandpass filters have a center frequency of 220 Hz to 875 MHz.

Tusonic makes a wide line of EMI/RFI filters including both AC and DC line models, surface-mount filters, feed-through filters, and custom filters. Other EMC products carried include ceramic variable trimmer capacitors, and radial leaded disc, tubular, and WEECON Plate capacitors.