Advance Cleaning Inc.'s method of window cleaning gives you the benefit of our special four step process. First we wet down the window, then we scrape the window with our special 3 ca. tool to remove all particulate matter such as paint, glue, water spots, bird droppings, tree sap, and other . We then use our special strip washer to wash the window and then follow-up with a squeegee to leave the window sparkling clean.