Ruko Knives Sharpening Pen Features The Ruko Knives Sharpening Pen centers on a 4 inch retractable diamond rod rated at 400 grit fine enough to refine an edge without removing excessive material. The rod retracts fully into the pen body when not in use protecting both the diamond surface and the user s pocket from accidental contact. A rounded and a flat edge give the sharpener versatility across different blade grinds while a dedicated groove handles fish hooks and serrated edges that a flat stone cannot easily reach. This combination makes the pen useful well beyond a single blade style. A pocket clip built into the pen allows it to ride securely in a pocket tackle box or pack keeping it within reach whenever an edge needs quick attention. The stainless finish on the pen body resists corrosion from repeated exposure to moisture a common concern for anglers and hunters working near water or game. Weighing just 0.16 ounces it adds virtually no bulk to a kit yet solves a real problem in the field. For anyone who carries a fixed or folding blade and wants a lightweight way to maintain its edge the Ruko Sharpening Pen is a practical addition. RUKO Knives Sharpening Pen Specifications Manufacturer: RUKO Knives Model: Sharpening Pen Color: Stainless Overall Length: 4 Material: Diamond Includes: Pocket Clip Weight: 0.16 oz Available At: GrabAGun