The AT-601 from RLC Electronics is a RF Variable Attenuator with Frequency DC to 1 MHz, Attenuation Range 0 to 90 dB, Attenuation Step 10 dB, Attenuation Accuracy .2 to .5 dB, Power 1 W. Tags: Module with Connectors, Rotary. More details for AT-601 can be seen below.