English: Shelf with various hair colours (hair dyes) in a hairdresser shop in Germany (2023), whereby the shelves are originally intended/sold as single columns for audio CD storage. Each colour is in a different tube which comes in a rectangular cardboard package. In the shelf, the packages as well as a lot of tubes can be recognized, which are lying on or close to their packaging. This is done because the colours can only be precisely identified by the colour code which is in large letters printed on the cardboard, but which is not immediately recognizable on the tube. Hence, by keeping the packages, the hairdrsser can find a certain colour tube much faster than if only the tubes would be stored in the shelf.