I have had many rulers over the years. wood, steel, aluminium. Each of them has its advantages and disadvantages. I like aluminum best for its lightness and the ability to recycle 100% of the material at the end of the product life cycle. The main disadvantage of aluminum rulers is the fact that aluminum itself is a very soft and malleable metal. If you don't take proper care of them and hang or store them in a specific place after each use, they may bend or wrinkle. Also, other aluminum rulers