The WLKE4-10-20-50-8000-1 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 10 / 20 MHz, Stopband Frequency Chosen Fco x 1.15 to 8 GHz, 3 dB Cutoff Frequency Choice of 10 to 20 MHz, Insertion Loss 1 to 1.7 dB, Rejection 50 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLKE4-10-20-50-8000-1 can be seen below.