The DC 22-BQB-(***-***)-B-(**) from The Waveguide Solution is a Waveguide Coupler with Frequency 26.5 to 40 GHz, Coupling 10 dB, 20 dB, 30 dB, 40 dB, Directivity 15 dB. Tags: Broadwall Coupler. More details for DC 22-BQB-(***-***)-B-(**) can be seen below.