The FN-3339W from Filtronetics is a Low Pass RF Filter with Frequency DC to 2100 MHz, Stopband Frequency 2630 MHz to 6.5 GHz, 3 dB Cutoff Frequency 2100 MHz, Insertion Loss 0.25 dB, Rejection 40 dB. Tags: Module with Connector. More details for FN-3339W can be seen below.