The BSF-280M from RF Bay is a Band Stop Filter with Stopband Frequency 255 to 310 MHz, Insertion Loss 0.5 to 2.5 dB, Rejection 35 to 50 dB, Power 0.5 W, VSWR Input 1.60:1, 2.00:1. Tags: Module with Connectors. More details for BSF-280M can be seen below.