The WLJ9-185-300-40-3000-100 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 185 / 300 MHz, Stopband Frequency Chosen Fco x 1.125 to 3 GHz, 3 dB Cutoff Frequency Choice of 185 to 300 MHz, Insertion Loss 0.7 to 1.15 dB, Rejection 40 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLJ9-185-300-40-3000-100 can be seen below.