Interlocking structural members

Claim 1

A STRUCTURAL ASSEMBLY WHICH COMPRISES: A FIRST STRUCTURAL MEMBER HAVING A PAIR OF ALIGNED SLOTS SPACED FROM EACH OTHER SLOTS HAVING A RELATIVELY WIDE AND A RELATIVELY NARROW PORTION; A SECOND STRUCTURAL MEMBER HAVING A WEB CARRYING A PAIR OF LUGS HVINSG HEADS OF A SIZE AND SHAPE TO FIT IN SAID WIDE PORTION OF SLOT, BUT OF A SIZE AND SHAPE DIFFERENT AND LARGER THAN SAID NARROW PORTION, SAID HEAD BEING SECURED TO SAID SECOND STRUCTURAL MEMBER BY A NECK PORTION OF A SIZE AND SHAPE TO SLIDE IN SAID NARROW PORTION OF SAID SLOT, A RESILIENT LATCH STRUCK FROM SAID WEB AND INTEGRALLY ATTACHED AT ONE OF ITS ENDS THRETO; THE OTHER, FREE END BEING DISPOSED BETWEEN SAID LUGS AND HAVING THE TERMINAL END THEREOF BENT OUT OF THE PLANE OF SAID WEB TOWARD THE SIDE CARRYING SAID LUGS, SAID FREE BENT END POSITIONED TO ENGAGE SAID FIRST STRUCTURAL MEMBER INTERMEDIATE SID SLOTS WHEN SAID LUGS ARE INSERTED INTO THE WIDE PORTIONS OF SID SLOTS, AND STRUCTURAL MEMBERS BEING RELATIVELY SLIDABLE TO CAUSE SAID LUGS TO MOVE INTO ENGAGEMENT WITH THE NARROW PORTIONS OF SAID SLOTS WITH THE FREE BENT END OF SAID LATCH AUTOMATICALLY MOVING INTO ENGAGEMENT WITH ONE OF SAID SLOTS WHEN SAID LUGS ARE MOVED ADJACENT THE CLOSED ENDS OF THE NARROW PORTIONS OF SAID SLOTS, THE FREE END OF THE SAID LATCH PREVENTING SAID STRUCTURAL MEMBERS FROM LATERAL MOVEMENT WHEN ENGAGED WITH SAID ONE SLOT.