The AT-BPF-232238-04 from AT Microwave is a Waveguide Filter with Frequency 232 to 238 GHz, Insertion Loss -4 to -2.5 dB, Operating Temperature -40 to 85 Degree C, Rejection -25 dB, Rejection Frequency 170 to 260 GHz. Tags: Band Pass. More details for AT-BPF-232238-04 can be seen below.