Stockmar Dual Pencil Sharpener – Lime Wood This Stockmar sharpener is suitable for safe sharpening both thick and thin (color) pencils with a triangular and hexagonal shape. The metal grinder, for extra strength, is recessed into the lid and is completely sealable. The metal grinder includes two steel blades designed exclusively for STOCKMAR. The honeycomb-shaped tray is manufactured from FSC certified lime wood. The steel blades are very easy to change by means of an easily accessible screw.