The 2701B Programmable Precision DC Voltage Standard features four voltage ranges of 1.2, 12, 120, and 1200 volts with 6 digit resolution. The 2701B accuracy is +/- 10 ppm + 4ppm of range + 2 uV. Load regulation is 10 ppm from no load to full load (20 mA). A proprietary design in the 2701B eliminates the contribution of switch resistance to divider accuracy and stability. Option TL-3 adds a GPIB interface to the 2701B.