The advanced HANNA GroCheck Combo provides continuous testing of both pH and total dissolved solids (TDS). A double-junction electrode with nonclogging Teflon diaphragm measures pH from 0.0 to 14.0 with a set point range of 3 to 7. The rugged TDS probe provides automatic temperature compensation and measures from 0 to 1,990 ppm with a set point range of 500 to 1,600 ppm. The state-of-the-art GroCheck Combo comes with a 12-volt adapter, requires no batteries and includes a wall-mount bracket for hands-free readings. It includes a two-year warranty on the meter and a six-month warranty on the electrode.