Review on Aluminum Medium Duty Storage Shelving With Dual Post Design And Press Board Shelves - 48 X 18 X 72 Inches By Amazon Basics by Wade Meeks

Well they are fine for the price but If you get the split ones where you can do two short shelves they are a bit scary as a single tall unit. The top vertical support just sits on the bottom with only the horizontal pieces to hold them in place, as they span both. Having said that I wasn't able to collapse them but I'll reinforce to be safe.Also there is no locking mechanism to prevent the horizontal supports from lifting so they rely on tension and weight.The shelving is crapboard which will surely dip in the middle at some point.What was sent to me was missing parts but amazon guy sent another to scavenge parts from and did this quickly. Nice.They are pretty cheap and will work for what I'm doing with them.