HIOKI, Benchtop Digital Multimeter

HIOKI DM7275 Precision DC Voltmeter
7-1/2 Digit DC Voltmeter for R&D to Production Lines
  The DM7275 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.

HIOKI DM7276 Precision DC Voltmeter
7-1/2 Digit, 9 ppm High Precision DC Voltmeter for Lithium-ion Batteries
  The DM7276 Precision DC Voltmeter delivers superior measurement accuracy of 9 ppm (0.0009%), an accuracy level that is demanded by advanced applications such as aging tests of lithium-ion batteries.