Jewel case

Optical disc packaging is the packaging that accompanies CDs, DVDs, and other formats of optical media. Most packaging is rigid or semi-rigid and designed to protect the media from scratches and other types of exposure damage.

A jewel CD case is a compact disc case that has been used since the compact disc was first released in 1982. It is a three-piece plastic case, measuring 142 by 125 by 10 millimetres (5.59 in × 4.92 in × 0.39 in), a volume of 177.5 cubic centimetres (10.83 cu in), which usually contains a compact disc along with the liner notes and a back card. Two opposing transparent halves are hinged together to form the casing, the back half holding a media tray that grips the disc by its hole. All three parts are made of injection-moulded polystyrene.

The front lid contains two, four, or six tabs to keep any liner notes in place. The liner notes typically will be a 120 by 120 millimetres (4.7 in × 4.7 in) booklet, or a single 242 by 120 millimetres (9.5 in × 4.7 in) leaf folded in half. In addition, there is usually a back card, 150 by 118 millimetres (5.9 in × 4.6 in), underneath the media tray and visible through the clear back, often listing the track names, studio, copyright data and other information. The back card is folded into a flattened "U" shape, with the sides being visible along the ends (often referred to as the spine) of the case. The ends usually have the name of the release and the artist, and often label or catalogue information printed on them, and are designed to be visible when the case is stored vertically, 'book-style', on shelves.

The back media tray snaps into the back cover, and is responsible for securing the disk. The center is a circular hub of teeth which grip the disc by its hole. This effectively suspends the disk in the middle of the container, preventing the recording surface from being scratched. The media tray was originally constructed of a flexible black polystyrene, but many newer trays use a more fragile transparent polystyrene. This allows the reverse of the back card, which is usually used for additional artwork, to be visible. This format did not become common until the mid-1990s.

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