AquaSock is a special water-removing chemical that is contained in a weighted, sock-like bag that has been designed to be inserted into an accessible filler inlet of a fuel tank, where it rests on the tank bottom (where the water is always present, it being denser and heavier that the fuel) for 24 hours. Using the retrieval string provided, the customer removes the water-only soaked, and now swollen sock, thereby eliminating the destructive water from the tank. More industrial strength, can pull out up to 28 oz. of water from your fuel tanks and will fit in an access hole of no smaller than 2 1/2" in diameter.