Hioki DM7275 [DM7275-03] 7-1/2 Digit, 20ppm High Precision DC Voltmeter with RS-232C Interface. The Hioki DM7275-03 Precision DC Voltmeter delivers superior measurement accuracy of 20 ppm (0.002%), an accuracy level that is demanded by advanced applications such as aging tests of lithium-ion batteries. Other key features include contact check to maximize measurement reliability, binning and temperature compensation, making the voltmeter ideal for developing and manufacturing Li-ion batteries, electrical double-layer capacitors, electric vehicle components, and other next generation devices.