The WLK3-30-50-60-3000-20 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 30 / 50 MHz, Stopband Frequency Chosen Fco x 2.7 to 3 GHz, 3 dB Cutoff Frequency Choice of 30 to 50 MHz, Insertion Loss 0.4 to 0.5 dB, Rejection 60 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLK3-30-50-60-3000-20 can be seen below.