by special construction of the frame members

Full Title

Special arrangements or measures in connection with doors or windows > for providing ventilation, e.g. through double windows; Arrangement of ventilation roses > by special construction of the frame members

Classification Context

Section:

FIXED CONSTRUCTIONS

Class:

DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS, IN GENERAL; LADDERS

Subclass:

FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES, OR LIKE ENCLOSURES, IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES