Product function: 1. Neutral line/live line detection: the test result LED red light and green light indicate live line, green light indicates neutral line. 2. Detection along : LED light on means is unblocked, LED light off means is disconnected. 3. Wire switch: if the plug and the inner core of the wire are intact, the light will be on, and if it is not on, it means that the core wire is in poor contact. 4. Uses: can be used in electronic factories, electrical appliances, car maintenance, household, etc., widely used Battery model: LR41 X 3 Measuring range: voltage 24-250V color:As shown Material:plastic Package Contents: 3 x Voltage Detector Pen Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. 5. Self-checking LED high-brightness bulbs: high-brightness works smoothly and is still clearly visible in the sun 1. High hardness and good electrical conductivity 2. Maintenance electrical measurement / screwdriver assist 4. Fully insulated anti-fall material, and improved performance 3. Humanized clip design for easy electrical maintenance and portability