The BRF-1200-100-L5 from COTS RF is a Band Stop Filter with Stopband Frequency 1150 to 1250 MHz, Bandwidth 100 MHz, Insertion Loss 1 dB, Rejection 60dB @ 1200 MHz, VSWR 2.00:1. Tags: Module with Connectors, Notch Filter. More details for BRF-1200-100-L5 can be seen below.