West Marne -100 degreeF Premium Marine Antifreeze provides the ultimate in cold weather and corrosion protection. Winterizing your boat for the off season is an excellent way to protect your investment and avoid costly repairs in the spring. West Marine -100 degree (-73 degreeC) Antifreeze provides the ultimate in cold weather and corrosion protection for potable water systems, sanitation systems and all engines. Ideal for regions with expected winter lows below 0 degreeF, this non-toxic formula uses pure virgin propylene glycol for quality and effectiveness. An added benefit of using non-recycled propylene glycol is that residual smell and tastes are reduced. Corrosion inhibitors have been added to prevent damage to metal engine components and seals. This antifreeze is alcohol free and will not evaporate and leave engine parts and areas of pooled water less protected later in the winter. The bright triple died blue-green color lets users know when antifreeze has traveled through water lines, sanitation system lines or engine cooling systems; and also serves as an indicator when flushing systems in the spring. For winterizing both engine and water systems, look to West Marine Engine and Water System Antifreeze for a safe, effective, ready-to-use solution.