The EMA4D1791P118C50D from ECHO Microwave is a Band Pass Filter with Frequency 1.73 to 1.85 GHz, Insertion Loss 1.4 dB, Rejection 48 to 50 dB, Return Loss 12 dB. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for EMA4D1791P118C50D can be seen below.