Abstract: A collapsible, reusable, general purpose shipping box is made from an inexpensive polymer composition, and can be mass produced by extrusion or coextrusion. The boxes are extruded or coextruded in an almost wasteless production as endless webs of inner layouts and outer layouts, which are folded into respective configurations with one of the configurations being outer one and another inner one. The enclosure is assembled by inserting the inner configuration into the outer one and snap-connecting the complementary male-female locking elements already extruded into the layouts. An extruded web may be many layouts wide as a given extruder and die allow. The boxes can be easily assembled from substantially flat and rectangular layouts at the point of packaging, either by hand or by using a slightly modified and currently widely used box erection machine, and as easily disassembled for transportation and cleansing at the point of unloading.