You've got it! A pop-up trundle does exactly what is says — pops up to create more space (or combine for a bigger bed). 1.A metal twin daybed with trundle to prove less is definitely more.

DURABLE STEEL CONSTRUCTION: Featuring an all-metal frame and steel slat support ... CONVENIENT STORAGE OPTION: Simply lift the pop up trundle bed of this daybed to king convertible bed to access ...