APPLICABLE MATERIALS. SpeTool 3D engraving bits, suitable for 2D/3D carving Hard wood, Plywood, Soft wood, OAK, MDF, Aluminum, Alloy Copper and Acrylic etc. 2-FLUTE DESIGN: Each tapered end mill is crafted with a 2-flute, ball nose and spiral design, ensuring smooth and efficient cutting through various materials.