The BSF-955MS1 from RF ONE Electronics is a Band Stop Filter with Stopband Frequency 0.9433 to 0.96 GHz, Insertion Loss 2.5 dB, Rejection 40 dB, Power 40 W, Return Loss 10 dB. Tags: Module with Connectors, Cavity Filter, Ceramic Filter, LC Filter. More details for BSF-955MS1 can be seen below.