This unique paste can be used with a measuring gauge, rod or calibrated line to determine gasoline level. Gasoline gauging paste will determine levels of gasoline, naptha, kerosene, gas oil, crude oils and jet fuels. After use, the paste can easily be wiped off with no residue. Apply the paste in the area that the level is expected to appear. When the paste comes in contact with water it will immediately change from a light pink to bright red, marking the level. 2.5 oz. plastic jar. Store between 35° F and 115° F for preservation of product.