The Pieces: The system consists of basically feet, poles, shelves, and caps. There are 3 pole sizes, large, medium, and small. The poles have a male threaded rod at the top and a female threaded insert at the bottom. This allows the poles to be combined in many combinations to make different lengths—bigger than your print size—and to screw the feet on the bottom and the caps on top. You can add any number of shelves. The poles come in three sizes: small, medium, and large.