https://www.dolphmw.com/products/waveguide-attenuators/ Dolph Microwave offers a series of rectangular microwave fixed attenuator. Typical Attenuation values are 3dB, 6dB, 10dB, 20dB and 30dB (other attenuation values available, consult sales engineers for details). The assembly construction includes a precision element for optimum electrical performance, but note that Attenuation vs. Frequency can vary greatly depending on the attenuation at a given frequency. For more, please contact.