After boating early in the season, our boat became stained green due to the amount of moss in our local pond. I tried several different products and resolved myself to taking it to a shop to haw the hull buffed white again. Happened into a local boat retailer and asked if there was something available to remove a stain from a hull. The clerk quickly picked up a bottle of BLAZZIN and stated that this will do It. I reluctantly made the purchase, got home and WOW! It seems that if you so much as hold the container next to the stain that It begins to disappear. Gone In 5 seconds or less……Great product! No Hassle! Rick