Abstract: A book-like storage container for cassettes or the like is formed from a single thermoplastic sheet of PVC plastic which has a pair of stackable trays formed on an inner face thereof that are connected together by an integral spine in side-by-side relation. Each tray is defined by C-shaped walls and the spine has flanges adjacent each end thereof for interlocking with the interfitting walls of the trays when the holder is in a closed position to form an enclosure therein. The PVC sheet has a living hinge defined therein along the connecting edges of the spine and each of its respective trays. In a preferred embodiment, a second thermoplastic sheet of flexible vinyl is placed back-to-back with the PVC sheet and thermally bound thereto about the sheets' peripheries. The PVC sheet is notched at the intersection of each living hinge and the periphery of the PVC sheet, so that when the peripheries of the PVC sheet and vinyl sheet are thermally bound together, there is no thermal seam at those notches.