Max Flow Air Brick with a painted black finish.
Robust and Heavy Duty, Made by Hand with large openings to allow maximum free air flow .
Although not a perfect fit, duct tape can be used to adjoin this imperial sized air brick to a metric sized Plastic cavity wall duct. This item known as a Cavity Horizontal Extension (CAVHEXT3) can be used to transfer air through the wall to an internal grille such as the Union Jack Vent (UJ3) or the Daisy (DAY104). Mesh cannot be fitted in this air brick but is more suited to be installed behind the internal grille (and it can be regularly removed for cleaning) were it serves to prevent bugs entering the rooms and reduces draughts, albeit reducing the free air by 1/3rd.
Please note that these product properties are not a replacement for the manufacturer's literature and it is always recommended that Cast Iron Air Brick Company is consulted before specifying.