This professional digital insulation tester has stable performance and reliable result. It adopts high converter ratio inductance energy storage low consumption DC voltage converter, to change 9V voltage to 100V/250V/500V/1000V DC voltage. Large LCD screen with switchable backlight, easy to read.Specifications?:Brand name?: Color: Black + OrangeMaterial: PlasticDisplay: LCD screen with backlight, 1999 (3 1/2 digits) Range control: Manual rangeLCD size: 90 * 38mm / 3.5 * 1.5"Voltage output: DC 100V / 250V / 500V / 1000VOutput current: 250V (R=250k)2mA, 500V(R=500k)2mA, 1000V(R=1M)2mA Insulation resistance range ():?? 250V?: 0.1M20M, 20M500M (4%+2digits) 500V?: 0.1M50M, 50M1000M (4%+2digits)1000V?: 0.1M100M, 100M2000M (4%+2digits) Short circuit current?: 2?mAMedian resistance?: 2?MTerminal position?: L, E, ACV, G(750?V)AC voltage (V): 1?V-750?V (1.0?% at 6 digits) Low battery indication?: YESLED backlight?: YEShigh Voltage indication?: YESPower supply: 6 batteries AA 1.5?V (not included) or DC 12V power adapter (NOT included) Operating Temperature/Humidity: 040, 3085%RHStorage Temperature/Humidity: 050, 3085%RH Item Size: Approx. 170 * 125 * 60mm / 6.7 * 4.9 * 2.4in??Item weight?: 541g / 19.1ozPackage size?: 21.5 * 18 * 8cm / 8.5 * 7.1 * 3.1in Package weight: 844?g / 29.8?ozPackage List:1 * Digital Insulation Tester1 * Pair of 10A Test Leads2 * Alligator clips1 * Storage bag 1 * User manual (English)