The L050XF9S from Knowles is a Low Pass RF Filter with Frequency DC to 4 GHz, Stopband Frequency 6 to 16.0 GHz, 3 dB Cutoff Frequency 5 GHz, Insertion Loss 1 dB, Rejection 35 dB. Tags: Surface Mount, Ceramic Filter. More details for L050XF9S can be seen below.