Corrugated fiberboard, or combined board, has two main components: the linerboard and the medium. Both are made of a special kind of heavy paper called containerboard. Linerboard is the flat facing that adheres to the medium. The medium is the wavy, fluted paper in between the liners.

The following illustrations demonstrate the four types of combined board:

*graphics accompanied each of the following text*

Single Face One medium is glued to one flat sheet of linerboard.

Single Wall The medium is between two sheers of linerboard. Also known as Double Face.

Double Wall Three sheets of linerboard with two mediums in between.

Triple Wall Four sheers of linerboard with three mediums in between.