The CA4-20/NFD from MCLI is a RF Variable Attenuator with Frequency 5.9 to 6.5 GHz, Attenuation Range 20 dB, Attenuation Accuracy 1 dB, Power 5 W, Peak Power 64.77 dBm. Tags: Module with Connectors, Continuously Variable, Rotary. More details for CA4-20/NFD can be seen below.