... store 500 groups (Relative to average times32~1 ) information including single measured value, mean value, testing data, impact direction, impact ... the immediate printing function. It can save data permanently.NI-MH rechargeable battery as the power source. With rechargeable battery, ... 0.5) mm, diameter is 30mm Battery pack: 6V NI-MH Battery charger: 9V/500mA Continuous working period: about 150 hours ...