Clear Scale: The metal screw extractor hood has etched high visibility scales for quick user identification and access. Chromium Molybdenum Steel: The screw extractor is made of high quality molybdenum steel which is wear-resistant, non-deformable and durable. Hex head: The screw extractor hood has a hex head which is mainly designed for applying maximum torque using sockets and wrenches. Left Spiral Design: The left screw extractor design provides extra gripping force and faster wire speed, making your work faster and easier. Storage Box: The screw extractor kit comes with a plastic case for storage, which is easily accessible and not easy to lose.