Urine Stain Eraser is specially formulated to remove that tough yellow stain on carpet and upholstery that is associated with pet stains. This product also eliminates any residual odors, it does not mask odors it eliminates them. Follow directions closely. DIRECTIONS FOR USE: DO NOT USE ON NATURAL FIBERS. 1. Always Pretest in an inconspicuous area and wait the appropriate time to test for color fastness before proceeding with treatment. 2. Thoroughly clean area to be treated. We recommend using a water claw and pre-treating with UTA Neutralizer. 3. Apply Urine Stain Eraser full strength directly to urine stain. 4. May take a few minutes two a few hours for stain to disappear. ( No need to extract after application) 5. Repeat treatment as necessary to remove the stain.