Metal Posts are a versatile block that can be used for many different purposes. These include but are not limited to Signal Mounting Brackets, Bridges, Trestles, Fences, and Support Pillars.
Metal Posts are unique in that they can be painted many different colors. By default, raw Metal Posts come in a rusty red color, however any kind of Dye can be used to produce painted Metal Posts. The downside being that removing a painted Iron Post will result once again in a raw Metal Post.
Removing any type of metal post using a Wrench (Electric or Bronze) gives you block #209 "Unnamed". This item cannot be crafted into dyed posts if combined with the original Metal Post.