Expansion chamber (confusional) with outlet on four sides Expansion chamber (confuser) with outlet to eight sides SWING grille with automatic drive 680x480mm / 630x430mm Nortes SWING grille with electric drive 685x450mm / 630x400mm SWING grille with electric drive 950x550mm 900x500mm Ventilation grille flat 310x260mm / 210x195mm Ventilation grille with throttle 500x260mm / 400x200mm Ventilation grille with air damper with 35° inclination angle 540x300mm / 405x195mm