The 4205-31.5 from Weinschel by Spectrum Control is a RF Variable Attenuator with Frequency 200 MHz to 6 GHz, Attenuation Range 31.5 dB, Attenuation Step 0.5 dB, Power 180 W, Insertion Loss 4 dB. Tags: Benchtop, Programmable, Digital, USB Controlled, Computer Controlled. More details for 4205-31.5 can be seen below.