Stackable and Collapsible:The storage bins with lids comes in flat station, just raise up 4 panels and tighten them together, and close the lid then you could start to use this plastic storage bins. No need tools to install them. The groove design on the stackable storage bins allow them stack up without tipping. When they are not in use, the collapsible storage bins can be folded up and stay under the sofa, will not take up space.