STEEL: the cutting edge is made of S50C alloy steel and HRC48 with high hardness, fast peeling speed, sharp and durable WIDE RANGE OF USES: Precision CNC proofing die, can accurately and easily strip the optical fiber without stripping the wire core. It is suitable for optical cable construction, network wiring, fiber-optic access boxes and patch cord factories SPRING AND HANDLE: Strong and tough spring, good durability and recovery performance, and labor-saving operation. The handle is non-slip and comfortable to hold PROOFREADING DEVICE: adjustable blade size, three-hole segmented peeling design, easy to use. (The factory has been adjusted, if no other problems are not to adjust) STORAGE SWITCH: It can be turned off after use to prevent being cut by the cutting edge and save space at the same time