Excellent sharpener: The retractable diamond sharpener is very suitable for grinding, cutting, sawtooth, etc. There are some grooves on the semi-circular surface, which can be used to sharpen hooks, needles, etc. Compact and portable: The pocket sharpener can be inverted and retracted. It can be adjusted to different lengths, shaped like a pen, and equipped with a shirt pocket clip for easy storage. Strong Material: The diamond sharpener is made of iron-coated emery, which has excellent wear resistance, corrosion resistance, high temperature resistance, high strength and impact resistance. The grinding layer is thin and smooth, which makes the tool well polished and prolongs the life of the tool. Ergonomic design: The telescopic grinding wheel is made of waterproof aluminum oxide, comfortable to hold and conforms to ergonomic design. When you sharpen, you will not feel tired and will not let the sharpening pen slip easily.