Shuts off automatically when battery cell is at proper level, no over filling. Features the double action fast flow valve tip that prevents after-drip. Stops surface discharge caused by a wet battery. Tough, polyethylene. Safe to use with battery acid. 2 quart capacity. Product Features:Shuts off automatically when battery cell is at proper level, no over fillingFeatures the double action fast flow valve tip that prevents after-dripStops surface discharge caused by wet batteryTough, polyethyleneTough, polyethylene construction; safe to use with battery acid; 2 quart capacity