Patent ID: 7093999

Claim:
A system for interlocking a plurality of items, such system comprising: a first item including a first planar base disposed beneath and supporting the first item, the first base having a plurality of edges, each edge having a first upper hook member defining a first upper groove and a first lower hook member defining a first lower groove, the first upper hook member being turned away from the edge and over the first base such that the first upper groove is disposed above the first base and opens in a direction facing away from the edge, and the first lower hook member being turned away from the edge and down under the first base such that the first lower groove is disposed beneath the first base and opens in a direction facing away from the edge; the first upper hook member and the first lower hook member each being U-shaped with the U being turned ninety degrees, parallel to the first base; a second item including a second planar base disposed beneath and supporting the second item, the second base having a plurality of edges, each edge having a second upper hook member defining a second upper groove and a second lower hook member defining a second lower groove, the second upper hook member being turned away from the edge and over the second base such that the second upper groove is disposed above the second base and opens in a direction facing away from the edge, and the second lower hook member being turned away from the edge and down under the second base such that the second lower groove is disposed beneath the second base and opens in a direction facing away from the edge; the second upper hook member and the second lower hook member each being U-shaped with the U being turned ninety degrees, parallel to the second base; and the second lower hook member being locked into the first upper groove, the second lower hook member and the first upper groove being sized to be forced into one another and to be held in place by the tightness of the fit while still being removable, wherein both the first base and the second base are rectangular and have four edges.