Penofin® Pro-Tech Wood Brightener 1 Gal FTECBGAPenofin Pro Tech Wood Brightener annihilates tough tannin stains and watermarks on all types of wood, decking, siding and fences; removes mill glaze. Penofin Pro Tech Brightener reestablishes the pH balance of your wood after stripping and cleaning and brightens gray weathered wood to bring back that mill bright color. Prepares hardwood for finishing Reduces mill glaze for better penetration Removes the gray Neutralizes tannin bleed Eight 300 Sq Ft