The 20825 3600-4200 from Microwave Filter Company is a Waveguide Filter with Frequency 3.6 to 4.2 GHz, Insertion Loss 0.71 to 1 dB, Rejection 45 to 90 dB, Rejection Frequency 3.4 to 4.4 GHz. Tags: Band Pass. More details for 20825 3600-4200 can be seen below.