The ZF200 from Antenna Technology Communications is a Waveguide Filter with Frequency 3.7 to 4.2 GHz, Insertion Loss 0.65 to 1.5 dB, Rejection 40 to 115 dB, Rejection Frequency 3.55 - 3.65 /4.25 - 4.35 GHz. Tags: Band Pass. More details for ZF200 can be seen below.