I was surprised, for the price, how small of a box it came in, but I see why sadly, the joiner pieces are plastic. The rest is thin, metal tubing, one of the joiner pieces as I was applying light pressure to it did, unfortunately partially crack. You have to snap pieces together and so slight pressure is needed. I put that rack on the top where the least weight will be, and proceeded to finish assembling it. It does the trick, but I am not sure how long it will hold up I was expecting it to be more sturdier for that price mark.