GEREE 12V Lithium Battery Capacity Tester Meter Display Panel Electric power Indicator Board Works for 12V battery, used for truck, RV, Golf cart or any battery operated unit. Warns when 30% of charge is left - Indicator displays Yellow. Red/Yellow flashing LED at 20% remaining charge. Must be connected during charging cycle. Dimensions: Cut-off: 1.5"x1", distance between holes: 1.75", depth: 1.5" .