Corrosion-resistant Tru-zero end hook for accurate measurements Mylar® is a registered trademark of DuPont Teijin Films for its polyester film. Only Dupont Teijin Films makes Mlyar® polyester film. 16" and 19.2" stud center markings simplify framing jobs. Cast-metal case is durable and suitable for heavy-duty use. Mylar® polyester film extends life of entire blade. Secure blade lock won't creep during measurements.