Abstract: The disclosed device comprises a pair of hingedly connected pocket formations receiving data cards which are derived by folding and connecting a plurality of initially integral panels, the panels being formed by cutting and scoring a blank of paperboard of relatively light gauge, and thereafter being folded and secured so as to provide the hingedly connected pocket formations in each of which an end panel of the blank forming the data card is confined and is accessible through an open end so as to enable it to be torn loose and to be moved to different positions in the pocket thereby enabling data imprinted thereon to be viewed through window openings in a wall forming panel on which related data may be imprinted.