Mitre Box, Aluminum by Excel Hobby Blade Corp. $10.28. Alum. Mitre Box This aluminum mitre box is just 6 inches long making it ideal for making precise cuts in all kinds of miniature work. Each unit has three slots, two at 45 degree angles and one at a 90 degree angle. For use with Excel razor saws. Excel is known for making high quality blades and tools for hobbyists around the world.