The EMA8J2840P120F40D from ECHO Microwave is a Band Pass Filter with Frequency 2.78 to 2.9 GHz, Insertion Loss 2.5 dB, Rejection 3 to 60 dB, Return Loss 15 dB. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for EMA8J2840P120F40D can be seen below.