Very sturdy.

I bought two sets of these for my garage. The base has tabs to bolt them to the floor, and the verticals have the rail notches on both sides for the shelves allowing you to leave out the bottom shelf to access the floor space. (I put my rolling toolboxes in there), and using the extra shelf rails to attach in between the units. Effectively having the storage of 3 units end to end, although you need 18 feet of space to place them all together like that.

Like others have said, these can be hit or miss out of the box. We purchased two of these units and even though both boxes looked okay, the one shelf was pretty mangled when we opened the box. There is no foam, no bubble wrap, nothing to protect anything from abuse. Our nearest Sam's is a 45 min drive so having to return the shelf was a hassle that a little foam could have prevented. Assembly is easy enough that one person can almost manage it themselves. Plan on using zip ties to hold the metal racks down, they slide off easily.

Shelves

Excellent

Easy assembly

Easy to assemble and it is really sturdy

Other than one being bent a little, nice shelving. Easy to assemble.

We love our storage rack! Very sturdy and very easy to put together! Bought 2

Sturdy, heavy-duty storage racks. Easy to assemble. Perfect to better organize garage!