The 3-in-1 tester is combined with the function of multimeter, test pen, voltage meter, can measure DC voltage, AC voltage, frequency, resistance, continuity, V~Alert, zero& fire line judgement, and more, which is suitable for electrical device maintenance.Specifications:Model: S1/ S1CL (Optional)Screen Display: S1: Black Words on White/ S1CL: White Words on BlackAutomatic measuring rangeFull measuring range overload protection.DC Voltage: 500V(0.8%+3), 0.1V resolutionAC Voltage: 500V(1.2%+3), 0.1V resolutionResistance: 10M(1.2%+3), 1 resolutionFrequency: 1000Hz(2.0%+3), 0.1Hz resolutionWork height: maximum 2000mDisplay: LCDMaximum display value: 2000 digits.Polarity indication: Self-indicating,"-"means polarity.Over-range display: "0L" or"-0L"Sampling time: The meter figures show about 0.4 secondsUnit display: Function and battery unit display.Automatic Power off time: 3 minutesOperational power: 1. 5V AAA battery.(not included)Battery low voltage indication: LCD display symbol.Temperature coefficient: Less than 0.1 x Accuracy/ Operational temperature and humidity: 0-40 / 32-104, 45% -80% RHStorage temperature and humidity: -10-60 / -4-140, 45% -80% RHMaterial: ABSItem Size: 150* 39* 18 mm/ 5.91* 1.54* 0.71 inchItem Weight: 65g/ 2.29ozPackage Size: 18* 8.3* 4.2cm/ 7.09* 3.27* 1.65 inchPackage Weight: 215g/ 7.58ozPackage List:1* Multimeter1 Pair* Test Pen1* Cloth Bag1* Chinese and English Manual