Armadillo Tough Collapsible Medium 4 Tier Metal Storage Shelf Unit with 1000 lb. capacity without wheels and 300 lb. capacity with wheels. This is a freestanding Shelf when wheels are not in use. Note that when wheels are added, weight capacity is limited to 300 lbs. This rack features a durable rust resistant powder coat finish and no tools are required for assembly. Each rack is collapsible for easy storage when not in use and includes an auto locking system. Shelves can hold up to 250 lbs. with weight evenly distributed without wheels and holds 75 lbs. evenly distributed when wheels are added.