https://youtu.be/wzpPjxDuXDo BST-9911B Pro portable Mini cordless magnetic energy screwdriver for laptop mobile phone repair of home appliances Power supply: 7 # Dry battery / AAA battery Type: cordless screwdriver, power screwdriver Rated voltage: 3.7V Frequency: N / A Nominal input power: N / A Max. Torque: 0.3-2N / m Unloaded speed: 160 rpm Dimensions: 243 mm * 75 mm * 42 mm Weight: 210g Application: mobile phone, laptop, computer, home appliance repair Use: lock the screws automatically Feature: high speed Battery: replaceable dry battery Working time: 8 hours Warranty: 6 months SURUBELNITA