The WRCT20-2581-2583-2603-2605-40-2 from Wainwright Instruments is a Band Stop Filter with Stopband Frequency 2.583 to 2.603 GHz, Bandwidth 20 MHz, Insertion Loss 2 to 4.5 dB, Rejection 40 dB, VSWR 1.50:1. Tags: Module with Connectors, Cavity Filter. More details for WRCT20-2581-2583-2603-2605-40-2 can be seen below.