SMD VM-1 Analog LED DC Volt Meter (12v) by MSD Ignition Input Range: 6v-30v Voltage Reading Range: 10.1v - 15.8v Accuracy: +/- 0.15v (due to the nature of a bar graph) 100% Analog circuitry allows for near instantaneous voltage accuracy versus a traditional digital voltage meter Response time from one end of range to the other is less than 200 milliseconds.