These 27 pane windows are used for industrial buildings, engine houses and roundhouses. Each window consists of a 9 pane sash mounted over a 9/9 double hung window. The prototype window would measure 44 inches x 140 inches and has an HO scaled opening of .53 inches wide x 1.63 inches high. Package includes 8 windows with pre-cut glazing. Injection molded in gray styrene.