B65D 5/004

Rigid or semi-rigid containers of polygonal cross-section, e.g. boxes, cartons or trays, formed by folding or erecting one or more blanks made of paper {stackable the container being formed by folding up portions connected to a central panel having ledges formed by extensions of the side walls the ledges being located between side walls and doubled-over extensions with separate means inserted between the doubled-over side walls for preventing lateral motion between stacked crates, i.e. the elements themselves not presenting stacking features, e.g. "n" shaped wires}