Assertion: box spring's foundation | /r/HasProperty | same size
Facets:
value: as the mattress
type: OTHER
value: usually
type: DEGREE
Source sentences:
text: The foundation is usually the same size as the mattress that sits on it, and while the mattress provides support to the human body, the foundation ensures that the mattress itself is properly supported to maintain a long comfort life.
text: The foundation should be the same size as the mattress without any visible gaps between the edges.