Usage Tips:Works with all 12V batteries. Wireless (Bluetooth 4.0) in10 meter Software included for Android and Receives notifications of battery conditions in Bluetooth range. Checks vehicle cranking system automatically while engine is starting. Checks charging system (alternator) Lists the time of each driving. Alerts mobile phone if detects abnormal data. Short-circuit and reverse connection protection. Data stored in battery monitor up to 35 days if out of sync. Automatic synchronization when in Bluetooth range. Compatible with all 12V vehicle batteries. Shows historical data graphically. Engie starting detection automatically. Free app for iOS and Android. Colour:black Material:plastic Package Contents: 1 x Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester Only the above package content, other products are not included. Note: Light 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.