Abstract: A self-ventilating infra-red ray heater having cooperating housing, endplate and internal reflector structure which results in standardized construction of parts which may be included in single or multiple element heaters. The invention seeks maximum utilization of inexpensive sheet metal components to obtain heaters of low manufacturing cost especially suitable for use in portable heaters which may be oriented to direct heat in any direction. In the aforenamed structure, an internal reflector is received in an arcade-type housing to form a space or jacket enclosing except for openings in opposite ends of the crown of the housing for communication of the space with the atmosphere. Preferably the end plates are formed with flanges which overhang the openings with clearance to protect against entry of unwanted materials into the space.