A clamp assembly for securing a pair of overlapping cross support members extending between two opposed side rails of a bed frame is provided. The clamp assembly includes a unitary clamp body, a leg assembly pivotally secured to the clamp body and a locking plate pivotally secured to the clamp body. In order to prevent the cross support members from sliding relative to one another, the leg assembly exerts force on the overlapping cross support members. The leg assembly may comprise a first leg pivotally secured to the clamp body, a plastic insert and a foot member. Alternatively, the leg assembly may comprise a first leg nestably secured to a second leg in order to increase the length of the leg assembly.