The EMA4D2504P130D30D from ECHO Microwave is a Band Pass Filter with Frequency 2.44 to 2.57 GHz, Insertion Loss 2 dB, Rejection 30 to 50 dB, Return Loss 15 dB. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for EMA4D2504P130D30D can be seen below.