Features and benefits: • Equivalent area of 6170mm2 per air brick • Unique stepped front grille greatly reduces the entry of wind driven rain • 6.5mm wide front grille openings comply with BS 5440 Pt 2 and British Gas requirements • Integral clip together facility allows multiple airbricks to be stacked to form 9” x 6” and 9” x 9” sizes • Available in a range of colours to blend in with various brick types • Very tough and robust • Durable and totally resistant to decay • 9” x 6” cowl version available to replace double air brick - provides an equivalent area of 11,000mm2 For use in conjunction with the telescopic underfloor ventilator for providing ventilation below suspended ground floors, or with cavity sleeves for ventilation through external walls to a building interior.