The Clarke CBBT1 is a small pocket-sized battery monitor/tester, capable of displaying battery power, voltage & temperature on a mobile device via the app (downloadable from Apple Store or Google Play Store). MAIN FUNCTION DESCRIPTION 1. Real-time display of battery power, temperature & voltage. 2. Automatically tests the starting & charging systems of the vehicle. 3. Sends alarm notification if the battery is abnormal. 4. App supports multi-device connection, 4 devices can be monitored at the same time. 5. Records the track, cost & driving habits of each trip which can be exported to an Excel file. 6. Records the last known parking position automatically & provides a car finder function through navigation. Please note that this is not a live tracking function. 7. Stores historical data (voltage, charge percentage & temperature) in the device for up to 30 days. Saves the data every 2 minutes. 8. Save unlimited historical data within the app. Please see the comprehensive manual to discover the full potential of this device. * Compatible with 12V Lead Acid Batteries: WET, MF, EFB, AGM, GEL, VRLA, Lead Calcium, SLA, 12V Li Fe PO4