The WLJE4-225-550-60-8000-1 from Wainwright Instruments is a Low Pass RF Filter with Frequency DC to 225 / 550 MHz, Stopband Frequency Chosen Fco x 1.24 to 8 GHz, 3 dB Cutoff Frequency Choice of 225 to 550 MHz, Insertion Loss 0.6 to 0.9 dB, Rejection 60 dB. Tags: Module with Connector, Lumped Component Filter, Chebyshev Filter. More details for WLJE4-225-550-60-8000-1 can be seen below.