The WLKE4-0.65-1-40-8000-0.01 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 0.65 / 1 MHz, Stopband Frequency Chosen Fco x 1.08 to 8 GHz, 3 dB Cutoff Frequency Choice of 0.65 to 1 MHz, Insertion Loss 0.6 to 1.2 dB, Rejection 40 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLKE4-0.65-1-40-8000-0.01 can be seen below.