Abstract: A coil spring supporting grid structure of the type used to reinforce the top surface of a box spring foundation unit is provided with formations on the longitudinal and transverse wires thereof, enabling a snap-in interconnection with a plurality of coil springs to form a spring unit assembly. Each coil spring convolute engaged by the grid structure is supported on a pair of upwardly extending formations from a pair of spaced parallel first wires and is locked in place by means of two downwardly depending formations from a pair of spaced parallel second wires which extend transversely with respect to the first wires to form the grid.

Abstract: A box spring mattress is supported a predetermined distance above a floor by a bed base including panels connected at their ends to form a rectangular frame and a pair of cross-supports resting crosswise on the edges of an opposed pair of notched panels. Each cross-support has a generally flat surface which is generally parallel to the floor and on which the box spring rests, and a downwardly pointing brace. The braces nest in the notches in the panels and the support surfaces are essentially flush with the unnotched portion off the notched edges of the panels. Each brace includes notches which lockingly connect with the notches in the panels so that the cross-supports cannot move laterally relative to the base. There are stop members at the opposed ends of each cross-support for restricting the lateral movement of the box spring relative to the base.