The ECA1747P75B20Q from ECHO Microwave is a Band Pass Filter with Frequency 1.71 to 1.79 GHz, Insertion Loss 1 dB, Rejection 20 dB @ 1665 to 1690MHz, Ripple 0.8 dB, Return Loss 20 dB. Tags: Cavity Filter. More details for ECA1747P75B20Q can be seen below.