The EMA4C2500P120D20A from ECHO Microwave is a Band Pass Filter with Frequency 2.44 to 2.56 GHz, Insertion Loss 1.5 dB, Rejection 20 to 40 dB, Return Loss 15 dB. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for EMA4C2500P120D20A can be seen below.