Nu-Calgon - Gas Leak Detector is a straw-colored liquid with a Brookfield viscosity of 120 cps at 26°C. It is a synergistic formulation that produces a viscous film, detecting refrigerant leaks as small as 1/2 ounce per year. It is non-corrosive, non-injurious, non-staining and harmless to skin. It has a solids content over 60% indicating a low-water content, and a favorable freeze-point (-20°F). It is available in 1 gallon bottles as well as 6 fl. oz. bottles with dauber applicator. It can be applied to suspect joints, especially "hard to reach" locations, with the dauber applicator. This applicator's rod is constructed of stainless steel; it will not corrode over time and the package will have years of shelf life. Gas Leak Detector has been servicing the air conditioning, refrigeration industry since the mid 1950's, perhaps being the first chemical leak detector in the industry. It is the most recognized and trusted chemical leak detector in the market.