The Olfa professional window film knife is the industry standard for cutting window film down to size. The blades are at a 45° angle to allow you the best angle for adjusting your window film without damaging the window's rubber and gasket. This is an essential piece of kit for a professional installer looking to create an exceptional finish for your installs. When you run out of blades, look no further than the Evowrap store for a handy replacement pack of snap-off blades.