The 2574-SMA from KR Electronics (A Division of NIC) is a Band Pass Filter with Frequency 17.5 to 22.5 MHz, Bandwidth 5 MHz, Center Frequency 20 MHz, Insertion Loss 3 dB, Rejection 40 dB. Tags: Module with Connectors, Lumped Component Filter. More details for 2574-SMA can be seen below.