Highest Grade Strontium Aluminate Pigments (grade 1, Brightness Rating2471 mcd/m2);Apply very thick, 1/16 or 4 oz per square foot. This container covers 18 square inches or 0.125 square feet.;Ideal to paint abusive environments like glow in the dark fishing lures, metal surfaces or signs;Often used for star ceilings, starscapes, and other space murals;Glows approximately two hours after full charge, can be recharged millions of times