Wire IdentificationPut your hand on the cap and touch the pole, insert the voltage measuring pen into the air, the electric pen lights up with double-color red and green lights, Non-Contact Voltage Tester with Dual Range is the live wire, lights up the green light for the zero line Precise SearchWhen the Non-Contact Induction Voltage Tester detects along the line, the green light will always be on at the position where the line is connected, and the disconnection point at the position where the light is off. Electric Pen Battery Self-InspectionAfter the battery is installed in the Non-Contact Voltage Tester, self-inspection is required. If the green light is on, the battery is fully charged, and the battery is low if the light is off or weak. Humanized DesignThe screwdriver electric pen is small and portable, the clip design is convenient for electricians to carry out maintenance, and the light can be lighted for easy identification High-Quality MaterialHigh-hardness chrome-vanadium steel material of the Voltage Tester has good conductivity, the main board professionally upgrades the chip control program, higher security, and longer life Product Parameters Product Type: LED Screwdriver Electric Pen Item model number: B12 Bit head material: vanadium steel bit head Measuring range: 24~250V Battery model: 3 LR41 button batteries Application: It can be used in electronics factories, electrical appliances, automobile maintenance, home furnishing, etc., with a wide range of uses Color: White Package includes: 1pc*Voltage Tester Pen (battery not included)