The BP2137A from PLEXSA MANUFACTURING is a Band Pass Filter with Frequency 21 to 37 GHz, Insertion Loss 1.5 dB, Rejection 45 to 55 dB, Upper Rejection 45 dB @ 39 to 55 GHz, Lower Rejection 55 dB @ DC to 20 GHz. Tags: Module with Connectors. More details for BP2137A can be seen below.