A collapsible cardboard box and lid. The box sides each comprise an outer face and an inner face flap connected by a fold-over region. Mitered edges of adjacent fold-over regions align to define mitered corners of the box opening periphery. Intermediate side flaps connected to the outer shell bottom are sandwiched between the side outer faces and inner face flaps, and a locking flap connected to one of the sides defines an interior bottom. The lid top face is connected to a first set of outer side faces connected by a fold-over region to inner side faces. One inner side face is connected to a top locking liner flap that extends to an abutment with the inner side face to define the lid interior. A second set of outer side faces connects to intermediate flaps sandwiched between the first set of outer side faces and inner side faces.