The QLF-6000-20 from Qualwave is a Low Pass RF Filter with Frequency 0.5 to 6 GHz, Stopband Frequency 6.5 GHz, Insertion Loss 2 dB, Upper Rejection 20 dBc @ 6.5 GHz, VSWR 1.80:1. Tags: Module with Connector. More details for QLF-6000-20 can be seen below.