The 58M4-20 from ARRA Inc. is a RF Variable Attenuator with Frequency 4 to 8 GHz, Attenuation Range 20 dB, Power 5 W, Peak Power 64.77 dBm, Insertion Loss 0.5 dB. Tags: Module with Connectors, Continuously Variable, Rotary, Motorized. More details for 58M4-20 can be seen below.