The BWLF-R19 from Sainty-Tech Communications Limited is a Low Pass RF Filter with Frequency DC to 0.19 GHz, 3 dB Cutoff Frequency 0.19 GHz, Insertion Loss 2.3 dB @0.19GHz, Rejection 20 dB @0.53GHz, 40 dB @0.8GHz, Power 30 dBm. Tags: Die. More details for BWLF-R19 can be seen below.