Features: Safe to Use: This pen-shaped sharpener is made up of fine diamond-coated steel rods that are not easily broken, and the grinding layer is fine and smooth, greatly extending the life of the knife. Application: Suitable for fish hooks, serrated and gut hooks. The sharpening rod has grooves specifically designed for fish hooks and the tapered portion of the rod is designed for serrated teeth and gut hooks. Quick sharpening, saves time and effort. Fast and Effective: Just a few sharpenings with our diamond steel and you'll have sharp knives again, just like new. Suitable for all kinds of knives, semi-circular and flat surfaces of sharpening steel for standard cutters. Durable Material: Strong and durable diamond material and aluminum alloy casing, efficient and sharp sharpening effect. The pen is designed to be lightweight and portable, and can be retracted into the handle for carrying or disassembled into the other end. For general sharpening work, hunting, outdoor adventure, fishing, etc. Customer Service: If you confront any problems about our products, please feel free to contact us, we are ready to help. We will solve your problems as soon as possible. Specification: Material: Diamond + aluminum alloy Color: Blue Weight: Sbout 50 grams Uses: General sharpening work, hunting, outdoor exploration, fishing, etc.