Stackable plastic container

Claim 1

AN OPEN-TOPPED RECTANGULAR CONTAINER ADAPTED FOR MOUNTING UPON AND IN LOCKED RELATION WITH A SIMILAR CONTAINER, EACH OF SAID CONTAINERS COMPRISING IN COMBINATION: (1) PAIRS OF INTEGRAL SIDE AND END WALLS, AND A BOTTOM WALL, (2) INTEGRAL CORNER WALLS ENCLOSING ANGLES OF 45* WITH AND CONNECTING THE ADJOINING SIDE AND END WALLS, TO PROVIDE CHANNELS OF SUBSTANTIALLY RECTANGULAR TRIANGULAR CROSS-SECTION AT THE CORNERS OF THE CONTAINER, (3) SAID CORNER WALL INCLUDING RELATIVELY SHORT END SECTIONS FORMING SHOULDERS AT RIGHT ANGLES TO THE ADJOINING SIDE AND END WALLS OF THE CONTAINER, AND (4) INTEGRAL ANGULAR SUPPORTING FEET EXTENDING OUTWARDLY FROM POINTS ADJOINING THE CORNERS OF SAID BOTTOM WALL AND EACH COMPRISING A PAIR OF SIDE WALLS AT RIGHT ANGLE TO ONE ANOTHER AND REGISTERING WITH THE RESPECTIVE CHANNELS OF THE CONTAINER, (5) THE FREE EDGES OF THE SIDE WALLS OF SAID FEET SLANTING OUTWARDLY TOWARDS THE CORNERS OF THE CONTAINER AND THE WIDTH OF SAID FEET BEING RELATED TO THE WIDTH OF SAID CHANNELS, WHEREBY TO CAUSE THE SIDE WALLS OF SAID FEET OF A FIRST CONTAINER, MOUNTED UPON A SECOND CONTAINER, TO ENGAGE THE ADJOINING LATERAL CHANNEL SURFACES AND TO CAUSE THE SLANTING EDGES OF SAID FEET TO ENGAGES IN LINE-TO-LINE CONTACT THE UPPER SHOULDER EDGES OF THE CORNER WALLS OF SAID SECOND CONTAINER.