Cleans and brightens in one step! Clean your teak naturally without harsh chemicals.  Does not raise wood grain. Just mix the recommended amounts of teak cleaner with water. Apply solution to wood, let rest 15 minutes, then brush lightly and rinse. Black algae, and mildew stains will disappear! This biodegradable solution will not harm other surfaces. Non-Chlorine.  A 16 ounce jar, makes 4 gallons of solution. For added protection, use the Iosso Water Repellent to safely seal without silicon or solvents.  No sticky residue.