PurCool Strips prevent sludge, odors, and overflow of condensate pans. Time release formula adheres to pan and fully dissolves over time. PurCool Green Strips use plant based suspending and dispersing action to keep drain pans clean and free flowing. Products are available for commercial, residential, and mini split applications. Sizes are based on system tonnage, with each strip lasting up to six months. Biodegradable and environmentally friendly. Will not harm aquatic life.