These rugged high performance high power Lowpass Filters are made with cutoff frequencies from 3MHz to 100MHz. Available in 50, 200 and 500 watt versions. The rapid cutoff and high attenuation these filters provide make them useful in many applications. These filters are suitable for harmonic reduction and bandwidth limiting on transmitters up to 500 watts. The special Impedance invariant design makes them compatible with all Antenna tuners. These filters meet applicable requirements of MIL-STD-810E and has been used on many Military HF Radios.