This is a multifunction instrument that can measure insulation resistance and AC voltage. It has fashionable appearance and stable performance, can be used for measuring electrical machinery, cable, electromechanical equipment, telecom equipment, electric power facilities and other insulation resistance. Features: This instrument applies automatic voltage release function, with high stability and reliability, with maximum 1999 counts, 0.1M-2000M insulation resistance measuring. It is suitable for measuring the insulation resistance of various electrical equipments and insulating materials such as transformers, motors, cables, switches, electrical appliances, etc. It is suitable for maintenance, repair, test and etc.. Rated output voltage is variable, easy to switch between 100V/ 250V/ 500V/ 1000V through the rotary knob. And it can measure AC voltage with the range of 1-750V. High voltage indication to remind you of safe operation; low battery indication to remind you of replacing batteries in time. The instrument has fashionable appearance and stable performance. With large digital LCD backlit display, easy to read. Battery powered or external DC 12V power adapter powered, satisfying different needs. Automatic shutdown after about 22min idle time to save power. Drop resistant silicone protective sleeve for protecting the tester from damage. Comes with a zipper storage bag for easy storage and portability. Note: 1. Please read the user manual carefully before use. 2. Size and color may be slightly different due to manual measurement and different light conditions. Thanks for understanding. Specifications: Color: Orange/ Blue (Optional) Material: ABS + Silicone Screen: LCD Backlit Screen Output Voltage: 100V/ 250V/ 500V/ 1000V Insulation Resistance Measurement: 0.1M-2000M Test Current: 1mA (250V/ 500V/ 1000V) Short-circuit Current: 1.8mA AC Voltage Measurement: 1~750V AC Voltage Frequency: 40-70Hz Jack Position: L, E Power Supply: 6 * 1.5V AA Battery (Not included) or External DC 12V Auto Shutdown: about 22min Maximum Display: 1999 Item Size: 170 * 129.1 * 63.4mm / 6.69 * 5.08 * 2.49in Item Weight (without battery): 543g / 1.20lbs Package Size: 21 * 17.8 * 7.8cm / 8.27 * 7.01 * 3.07in Package Weight: 860g / 1.90lbs Package List: 1 * Insulation Resistance Tester 2 * Test Pen 2 * Alligator Clip 1 * Storage Bag 1 * User Manual (English)