The Spyderco Tri-Angle Sharpmaker is a simple, reliable system for putting a consistent edge on knives and tools. Its ABS plastic base has keyed holes that hold the ceramic stones at fixed angles of 30° (15° per side) or 40° (20° per side), so all you do is keep the blade upright and draw the edge down each stone in turn. The kit includes two pairs of high-alumina ceramic stones: medium-grit brown stones for sharpening and fine white stones for a polished finish. The rounded edges of the stones handle serrated blades, and the corners and flats suit scissors, awls, fish hooks and many other tools. Aluminium safety rods protect your hands, and every part stores inside the base and lid. Supplied with an instruction book and DVD.