The QLF-4000-50 from Qualwave is a Low Pass RF Filter with Frequency DC to 4 GHz, Stopband Frequency 4.7 to 8 GHz, Insertion Loss 1 dB, Upper Rejection 50 dB @ 4.7 to 8 GHz, VSWR 2.00:1. Tags: Module with Connector. More details for QLF-4000-50 can be seen below.