The WLJ4-185-400-60-3000-100 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 185 / 400 MHz, Stopband Frequency Chosen Fco x 1.95 to 3 GHz, 3 dB Cutoff Frequency Choice of 185 to 400 MHz, Insertion Loss 0.3 to 0.35 dB, Rejection 60 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLJ4-185-400-60-3000-100 can be seen below.