Compucessory Jewel Cases, Starter Kit, w/ Base and 5 Cases, Assorted Unique storage system allows jewel cases to be used individually or stacked to create a custom rack. Cases interlock for stacking and can easily be removed for portability. Each case features a slide out tray for easy access to CDs or DVDs. Tray locks into place when used as a normal jewel case. Modular design provides unlimited expandability. Labels included for each case. Kit includes spinning starter base.