The WRCT40-1879-1880-1900-1901-50 from Wainwright Instruments is a Band Stop Filter with Stopband Frequency 1.88 to 1.9 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 WRCT40-1879-1880-1900-1901-50 can be seen below.