The AB4363B921 from Anatech Electronics is a Band Pass Filter with Frequency 4.28 to 4.43 GHz, Bandwidth 150 MHz, Center Frequency 4363 MHz, Insertion Loss 0.8 dB, Upper Rejection 60 dB @ 4500 MHz. Tags: Module with Connectors, Cavity Filter. More details for AB4363B921 can be seen below.