Lansky 9" Diamond Sharp Stick by Lansky. $23.92. Makes knife sharpening faster and more efficient than ever before. Safety guard. Fine diamond grit. Rubber over-molded non-slip handle. In addition to the traditional steel rod, Lansky takes the classic Buther's Rod style sharpener to a new dimension with a fine diamond grit bonded to a heavy-duty steel rod. Just a few strokes are all you need to put a factory-like edge back on your knives.