The BSF-750MS1 from RF ONE Electronics is a Band Stop Filter with Stopband Frequency 0.5 to 1 GHz, Insertion Loss 3 dB, Rejection 50 dB, Power 40 W, Return Loss 10 dB. Tags: Module with Connectors, Cavity Filter, Ceramic Filter, LC Filter. More details for BSF-750MS1 can be seen below.