1.Compatible with all 12V vehicle batteries and installed in the car battery Real-time monitoring via mobile phone app. 2.Check the starting system (cranking) at each engine start and check the starting voltage every hundredths of a second when the engine starts 3.Engine start is automatically detected and check the charging and starting systems (alternator) 4.Receive battery condition notification when you enter bluetooth range and notify mobile phone when some data is abnormal 5.View short circuit and reverse connection protection and voltage and charge information. When the user is close to the vehicle, the app does not need to be opened 6.Automatically syncs when entering Bluetooth range and data stored in battery monitor for up to 35 days if out of sync. 7.List the time of each trip and check historical data graphically. Specifications: Average Current1mA Input Voltage6-20V Operating Temperature-40-90 Dimensions5.6*4*1.6cm Voltage Accuracy(9~16V) 0.03V Bluetooth:4.0 Bluetooth Name:Battery Asst App NamBattery Asst Supported FunctionsShort-circuit Protection Package Includes: 1pc x Vgate Battery Assistant Bluetooth 4.0 Product Features: Easy to install on battery Real-time battery health monitor Tests vehicle cranking system Tests vehicle charging system Stores and displays historical data Save test records Automatic synchronization Free app (Android .IOS) download Monitor multiple device on your phone Alert notification Bluetooth 4.0 Battery Assistant is Suitable for: DIY users Battery service station Garage/workshop Tool store Vehicle/Battery manufacturer Package Includes: 1pc x Vgate Battery Assistant Bluetooth 4.0 How to Use It? 1.Open the car battery cover, find the battery positive and negative. 2.Screw the positive and negative, install the product's red and black connector to the positive and negative pole of the battery accordingly. Then tighten the screw. 3.Press the app on your phone, it should connect to the device. As it is Bluetooth (4.0), it does not need to pair and connect the automatic battery monitor automatically. 4.Release all permissions while running the app(Battery-Asst) 5. Check the feature details 6. When a red letter appears on the top left, please press to reconnect the Ble 4.0. 7. System configuration 8. Notification bar message