The 3245 SOLAR HiTESTER digital multimeter was developed with an emphasis on ecological considerations and safe design. The photovoltaic cell charges the lithium-ion main battery, which exhibits superb charging and discharging characteristics. Should the main battery charge become depleted, the hybrid power system automatically switches operation to the backup battery. Ecological considerations are satisfied without any of the typical inconveniences usually associated with solar-powered systems. Also, despite its vest-pocket size, the design conforms to CAT III safety standards for use on power lines. This new-style DMM has significant safety features and remarkably improved operability over previous designs.