Wet & Forget 48 oz. Xtreme Reach Hose End Refill for your Xtreme Reach Nozzle. It provides an additional 2,000 sq. ft. coverage, allowing you to quickly and easily treat any large outdoor surface including roofs, siding, decks, and high elevations without scrubbing or using bleach. Safe for use on virtually any outdoor surface, it works over time with the rain and wind to gently clean up green and black stains caused by moss, mold, mildew, and algae.