Duplex board, which is also known as Grey back or White back duplex boards, is a form of paperboard or cardboard with a double-sided grey or white color. Since it is made up of two layers, or plies, it is referred to as duplex board. Duplex board has a shiny coat finish on one side for superior printability.
It is commonly used to create boxes for a variety of small goods. For example, it is often used in pharmaceutical packaging.