DYNATEK Dyna Voltage Monitor DVM-1

Allows the user to track battery voltage, Primary use is determining when to recharge a battery in a total loss application; commonly found in drag racing, When the green light is on, the battery is fully charged; when the amber light is on, there is still sufficient voltage to operate the ignition and other accessories; when the red light is on, the battery should be charged as soon as possible, Measures 1-5/8″ L x 1-1/8″ W x 1/2″ H, Made in the U.S.A.