The FN-3338W from Filtronetics is a Low Pass RF Filter with Frequency DC to 1315 MHz, Stopband Frequency 1644 MHz to 5 GHz, 3 dB Cutoff Frequency 1315 MHz, Insertion Loss 0.25 dB, Rejection 40 dB. Tags: Module with Connector. More details for FN-3338W can be seen below.