Excellent Knife Sharpener: Our retractable diamond sharpening stone works well for sharpening knives, serrated blades, scissors, large kitchen knives, and smaller kitchen knives. The semi-circular surface features grooves that can be used to sharpen fish hooks, needles, and similar tools, helping restore sharp edges. Small and Portable: This pocket knife sharpener flips and retracts for convenience. It adjusts to different lengths, has a pen-like design, and includes a shirt pocket clip for easy carry and storage. Ideal for camping, outdoor adventures, hunting, and fishing. Sturdy Material: The diamond knife sharpener is made with iron-coated emery, offering excellent wear resistance, corrosion resistance, high temperature resistance, high strength, and impact resistance. The fine, smooth grinding layer effectively sharpens and polishes blades, extending their lifespan. Easy Grip: The retractable knife sharpening stone is constructed with waterproof aluminum oxide material. It features an ergonomic design for a comfortable grip, reducing hand fatigue and preventing slippage during use. Sufficient Quantity: One package includes two sets of diamond grinding point sharpening stones. Each set contains a pen-style case and a sharpening rod. Keep one set at home for kitchen knives and take the other set on the go for convenient sharpening whenever needed.