The EMA6E1227P30C20B from ECHO Microwave is a Band Pass Filter with Frequency 1.21 to 1.24 GHz, Insertion Loss 1.2 dB, Rejection 20 to 35 dB, Return Loss 15 dB. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for EMA6E1227P30C20B can be seen below.