Swimming Pool Winterizing Chemical Treatment Closing Kit - Up To 30,000 Gallons Swimming Pool Winterizing Chemical Closing Kit - Up To 30,000 Gallons 1 Quart Winter Treatment ensures clear water for closing 1 Quart Stain Control helps prevent and control algae stains and build-up 3 Pounds Non-Chlorine Shock kills micro-contaminants, algae, and pathogens Kit designed for pools up to 30,000 gallons