Product Specifications: Battery model: LR41 X 3 (included) Measuring range: voltage 70-250V Drill bit material: chrome vanadium steel Shell material: ABS Size: about 140x20mm/5.51x0.79in feature: 1. High hardness and good electrical conductivity 2. Repair power meter/screwdriver help 3. Humanized clip design for easy electrical maintenance and portability 4. Fully insulated anti-fall material, durable and improved safety performance 5. Self-controlling LED high-brightness lamps: high-brightness works smoothly and is still clearly visible in the sun Uses: Can be used in electronics factories, electrical appliances, car maintenance, households, etc., with a wide range of uses Package includes 1*Test pen Product Features: 1. Neutral/live wire detection: the test result LED red light and green light indicate the live wire, and the green light indicates the neutral wire 2. Detection along the line: LED light on means the line is unblocked, LED light off means the line is disconnected 3. Wire switch: if the plug and wire core are in good condition, the light will be on, if not, it means the core wire is in poor contact Comment: Due to different monitors and lighting effects, the actual color of the item may be slightly different from the color shown on the picture. Thanks! Please allow 1-2cm measurement deviation due to manual measurement. 【Detection】Please bottom pan with hand, positive terminal battery with tip pen, and negative terminal battery with other hand. When light is on, battery is fully charged, and vice versa. 【Find Breakpoints hand touches bottom pen, and tip pen touches wire. breakpoint is where light goes out. is to find breakpoints in daily household appliances such as rice cookers, computers, and plug-in boards, etc. 【Automatically Induction】As long as is close to insulation wire, plastic shell electrical appliance, etc., when light is on, means that is live. brighter light, higher voltage tested circuit, and vice versa. 【Self Check Function】In self-check before use, please hold pen tip with hand and tail with other hand. When light is on, means tester pen is normal and has sufficient power. No light indicates that battery needs to be replaced. Our tester pen is composed a and durable PVC Handle, screw rod, slotted point nut, spring, neon bulb tube, and resistance block, which ensure while using