Features: - Switch button to check battery capacity or voltage in real time and turn off - Alarm when battery capacity is less than 20% - Compatible with lead-acid, ternary lithium, lithium ion polymer, lithium ion 3-15 series, storage and water batteries - Not compatible with iron phosphate and lithium batteries, 1-2 Li batteries in series and more than 15 Li batteries in series - Operating voltage: DC 12-84V - Working current: 5 mA max. - Working temperature: 0-40 degrees Celsius - Material: ABS - Product dimensions: 61.3 x 33.3 x 13.5 mm - Mounting hole dimensions: 58.5 x 28.5 mm