Combined mortise and tenon joint feature

A one piece stowage bin (10) has a generally rectangular, polygonal open-fronted box-type structure. Right and left end panels (14) and (18) rise up from the sides of the bottom panel (12) to form side walls. Three fold lines allow the stowage bin (10) to comprise the rear lower panel (22), the rear upper panel (26) and the top panel (30) of the stowage bin. Tenons (51), (52), (53), (54), (57), (58), (59), and (60) extend from the margins of the right and left end panels (14) and (18). Mortise pockets (63), (64), (65), (66), (71), (72), (73), and (74) are formed in the side margins of the rear upper panel 26 and the top panel (30). The mortises and tenons create interlocking mortise and tenon joints that do not require a bonding adhesive. Right and left formed angle brackets (38) and (40) secure the right and left end panels (14) and (18) to the top panel (30). Rear upper panel edge margins (27) and (28) and the top panel edge margins (30) and (32) contain outwardly extended bulges in the region of the mortise pockets that define minimum edge margins around each mortise pocket. Right extending minimum edge margin bulges (81), (82), (83), and (84) are staggered relative to left extending minimum edge margin bulges (89), (90), (91), and (92). Protrusions (120) extend into the interior of the mortise pockets from the sidewalls thereof to extend into the interior of the mortise pockets. The protrusions are sized to form an interference fit with the tenon tabs through a combination of spring deflection of the protrusions by the tenon tabs and local material removal from the tips of the protrusions as the tenons are inserted.