The PDC-42181940-01 from Ducommun is a Waveguide Diplexer with Bandwidth 400 MHz, Center Frequency 17.9 GHz / 18.9 GHz, Frequency 17.7 to 18.1 GHz / 18.7 to 19.1 GHz, Frequency Band1 17.7 to 18.1 GHz, Frequency Band2 18.7 to 19.1 GHz. More details for PDC-42181940-01 can be seen below.