Description: Size InformationSmart Battery Monitor measures approx 6.9cm/2.72inch in diameterFunctionBattery Monitor is to calculate ampere hours consumed and the state of charge of a batteryFeatureSmart Battery Monitor has the basic display options, such as voltage, current, and ampere hours consumed, also displays state of charge, time to go, and power consumption in wattsEasy to UseSmart Battery Monitor with a quick install menu and a detailed setup menu with scrolling texts assist the user when going through the various settings.NoteFor Smart Battery Monitor, professional installation is required. Please consult a professional and follow all applicable electrical codes during installation Specification: material: plastic Size Chart: Diameter 6.9cm/2.72inch Package Includes: 1 Smart Battery Monitor Note: Please allow slightly errors 1-2cm differences due to manual measurement.