heat sealing machine to permanently seal the parts together the case comprises opposed sections joined by a spine with the edges of the case sections that come together when the case is closed being provided with interlocking half rounded members serving as a case closure application_number US 15840393 A description fig1 shows an end view of one form of plastic package or case 10 in accordance with the invention the case 10 comprises a base part 11 and a cover part 12 joined at the left side by spine 13 the position depicted in fig1 is with the case closed and with a possible video cassette or other object not shown enclosed within the case 10 fig2 shows the case 10 in its open position with any video cassette removed each case side is made up of a continuous wall 15 15 39 with opposite projecting portions 16 whose spacing is such as to allow a standard video cassette to fit inside the wells 17 formed by the walled region 15 a projection 18 close to the center on the base side 11 engages an opening in the video cassette when present the depth of each well 17 formed inside the wall 15 is such as to accommodate one half of the video cassette thickness so that when the case is folded into its closed position the top wall surfaces 19 can engage as shown in fig1 the spine 13 extends down the center of the case between both sides 11 12 the.