A display unit for displaying various flat or flat-packaged articles, such as greeting cards, magazines, brochures, and the like is provided. The display unit includes a molded backboard having a plurality of walls joined to one another by a plurality of horizontal channels and a snap-in retainer for holding the displayed articles which is easily inserted into and removed from the channel of the backboard. Additionally, the present invention relates to a method of making such a molded backboard and a mold insert tool for use in forming the channel of the backboard.