Plano 30.25"W x 14.25"D x 74.5"H 5 Garage Shelf HD Plastic Storage Unit, White, 375 lb Capacity

Ok, so here's the key to making this unit work -- All it takes is a hammer. I was not sure what the little black tubes were for so I threw them out & put the unit together without them. Just stick the shelves together -- loosely -- one by one -- and lightly HAMMER them into place until they're flush-straight. Tap them into position one by one. If the bottom shelf is not flush to the ground and makes the unit wobble -- hammer down the corners until they're flush to the ground. I suggest putting the heaviest stuff on the bottom shelf to keep the unit stable. You can also get two "closed" hooks from Home Depot. Screw the hooks into the wall -- one on each side -- then thread string through the hooks -- then around the unit vertical arms. That way it will never topple over. Great unit.