The two balls
It will provide a bright green indication if the battery is charged, a clear and bright red indication if the electrolyte level is low.
Advantages:
Determines the battery capacity at a glance.
Basing on specific gravity, indicates stable charging state.
Provides temperature compensation to assure accurate reading at any battery temperature.
Indicate a low electrolyte level
Reduces the demands fpr OCV(open circuit voltage) testing, thereby saving time.
Reduces customer warranty claims.
Improves end-user satisfaction.
