The 8311-137-6-F from Weinschel by Spectrum Control is a RF Variable Attenuator with Frequency 800 MHz to 3 GHz, Attenuation Range 63 dB, Attenuation Step 1 dB, Power 50 W, Insertion Loss 4.70 dB. Tags: Benchtop, Rackmount, Programmable, Digital, Computer Controlled. More details for 8311-137-6-F can be seen below.