Spray & Forget Super Concentrated Revolutionary Roof Cleaner with Hose End Adapter is your outdoor home improvement stain remover solution. The super concentrated cleaner tackles tough stains left by mildew, mold, algae, and moss. The 1-quart plastic container includes a hose sprayer adapter that easily attaches to any garden hose. To use, first check the forecast to ensure no precipitation in the 12 hours after application. Check that switch is turned to "OFF." Attach to the hose end sprayer, turn on water and move switch to "CLEAN" position. Apply a thorough coat to stained area, keeping the surface wet for as long as possible. DO NOT RINSE. Green stains will disappear in 1-3 days and black streaks and stains will continue to disappear with subsequent rainfall over 3-6 months. Apply this Spray & Forget exterior stain remover every 24-36 months or at first sight of new staining. Keeps cleaning long after application! Read and follow all label directions. Keep out of reach of children