DYNATEK Charge Monitor DCM-1

Charge Monitor
Allows user to track electrical system voltage on any vehicle with a normal 12V charging system, When the "normal" green light is on, the system voltage is normal and the battery is being charged correctly; if the "high" red light is on, the system voltage is too high and damage to the battery may result; when the "low" red light is on, the system voltage is too low and the battery is being discharged, The above indications are only valid with the engine running, Measures 15/8" L x 1" W x 1/2" H, Made in the U.S.A.