Precision 3-wire, simple 2-wire method to measure earth resistance, earth voltage and low resistance. 1. Model No.: ETCR3000C 2. Earth resistance measurement, Range: 0.010Ω~2000Ω 3. Earth voltage measurement,Range: AC 0~600V 4. Data storage: 400 sets 5. Alarm function: audible and visual alarm 6. Power Supply : DC 7.4V 2600mAh rechargeable lithium battery, battery charge full about 8.4V