The 211A from ACST GmbH is a Frequency Multiplier with Input Frequency 135 to 160 GHz, Output Frequency 270 to 320 GHz, Input Power 20 to 140 mW, Output Power 16.98 dBm, Frequnecy 135 to 160 GHz. Tags: Waveguide, Passive, Waveguide Multiplier. More details for 211A can be seen below.