Rytons Multifix Air Brick Terracotta 9x3 (215mm x 66mm) Free Area 77.5cm Robust interlocking air brick. Grille design allows a high air flow with low pressure drop performance. One size can form a unit 9×6, 9×9 etc. Textured finish maintains aesthetic appearance. Use with Rytons Periscope® Underfloor Ventilator PUFV and AirLiner® cavity liners 9×3, 9×6 and 9×9. U.V. stabilised to slow down the effects of sunlight. Please note: This item is a plastic component and therefore is not suitable for use within a) the external walls of buildings more than 11m high where people sleep on the premises (residential, institutional or hospitality) or b) external wall surfaces within 1m of the boundary if the building is 11m high or less, in England.
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