The G935 Combination Cavity Sleeve fits into the back of Manthorpe’s G930 Airbrick to ventilate through a standard cavity or solid brick wall. The 9" x 3" unit can be stacked to create a 9" x 6" and 9" x 9" alternative, and telescopes to fit cavity widths of 50mm to 100mm, with further extension possible through the addition of extra product units. Packs of 10 5 boxes available
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