The PBP-21.4 from Mini Circuits is a Band Pass Filter with Frequency 19.2 to 23.6 MHz, Bandwidth 4.4 MHz, Center Frequency 21.4 MHz, Insertion Loss 1.5 dB, Rejection 20 dB @ 29 MHz. Tags: Plug In, Drop-In. More details for PBP-21.4 can be seen below.