The Erika metal bed has a sturdy adjustable base so that the bed can be used with or without a box-spring to suit your needs. This feature allows for much storage space under the mattress base if used without the box-spring. Our metal beds are made in North America and are very high quality but at affordable prices. They are made of steel and are powder coated and come in twelve different color options (above shown in Oxidado). Come visit us in our San Francisco store and view these beautiful beds. If you have any questions, please feel free to call or email us--we're happy to help.