... 2%, Accuracy: better than ±1%Non-intrusive measuringNon-intrusive, clamp-on transducer, no pressure drop, no pipe disturbance.Wide ... English display, easy to operate.Large capacity battery Built-in rechargeable Ni-MH rechargeable battery, provide over 20 hours of continuous ... than ±1%Power Supply Built-in rechargeable Ni-MH battery (for 20 hours operation) orAC 220VPower Consumption 1.5WCharging ...