Exterior 450 Topcoat is a clear-drying finish suitable for vertical exterior surfaces, such as fences, patio furniture, entrance or garage doors.  It is not recommended as a deck finish.  Exterior 450 is fortified with UV absorbers to stabilize and protect the integrity of the finish, and built-in mildewcides to slow mold and mildew growth.  It performs well as a clear coat or as an optional topcoat.  Do not  use over light or white paints as yellowing may occur.  The UV Additive in 450 Clear will protect the integrity of the film, but will not prevent the wood from changing colour from sunlight
 
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