BG Windshield Washer Concentrate keeps windshield washer system ice-free to –144°F (–98°C) when used full strength. When diluted with three parts ordinary tap water, it will anti-freeze the washer solution to 0°F (–18°C). It contains an anti-corrosion compound which protects metal components in the system from rust and corrosion. For summer use, it may be diluted with six parts ordinary tap water. This solution will effectively remove bug stains and dirt from the windshield, leaving streak-free driving visibility.