HI-8427 pH/mV Signal Generator with Extension Cable

The Hanna HI-8427 is designed specifically to simulate pH and ORP electrodes and to confirm proper functioning of your meter. Standard pH electrode ranges are selectable with a dial on the front panel. The pH range is pH 0, pH 2, pH 4, pH 7, pH 10, pH 12 and pH 14 with the mV range being -1900 mV, -350 mV, +350 mV and +1900 mV.