The WLJE4-550-1000-40-8000-1 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 550 MHz / 1 GHz, Stopband Frequency Chosen Fco x 1.08 to 8 GHz, 3 dB Cutoff Frequency Choice of 550 MHz to 1 GHz, Insertion Loss 0.7 to 1.4 dB, Rejection 40 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLJE4-550-1000-40-8000-1 can be seen below.