The WRCT40-1909-1910-1930-1931-50-4 from Wainwright Instruments is a Band Stop Filter with Stopband Frequency 1.91 to 1.93 GHz, Bandwidth 20 MHz, Insertion Loss 3.5 to 6.5 dB, Rejection 50 dB, VSWR 1.50:1. Tags: Module with Connectors, Cavity Filter. More details for WRCT40-1909-1910-1930-1931-50-4 can be seen below.