Each unit will provide 3,000mm2 of free air flow. 275mm x 193mm.
eBay
4m X 4m Terrace Luxury Garden Gazebo Patio Cover Roof Canopy Louver Roof Aluminum Pergola
Aliexpress UK
TIMLOC FELT LAP VENTS. Free your loft from Condensation in a cheap and very easy to install manor. If further ventilation is required, install one lap vent into every rafter space at low level and/or into lap joints at higher levels.
eBay
Outdoor Swing Chair Awning Garden Waterproof Swing Canopy Roof Cover Outdoor Garden Swing Chair Canopy Roof Shade Swing Cover
Aliexpress UK
Felt Vents for Loft: Each unit will provide 3000mm² of free airflow into the loft space. Lap Vents for Loft: Can be fitted at joist centres ranging from 400mm to 600mm, suitable for most roofs. The arched design can withstand greater pressure and has multiple holes to greatly increase ventilation.
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1 Set Slanted Roof Pergola Brackets Wall Mount With Hardware Accessories For 4x4 Inch Outdoor Porch Gazebo Roof Pavilion Bracket
Aliexpress UK
Perfect fortile, slate, or shingle roofs, these vents are easy to install and ensureoptimal airflow in lofts and attic spaces. Keep your loft and roof spacesdry, well-ventilated, and free from condensation with these12 Felt Lap Vents.
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Felt Furniture Sliders Hardwood Floors - 4 PCS 6" x 3 1/2" Furniture Sliders - Heavy Duty Felt Sliders Hard Surfaces
Aliexpress UK
Manthorpe Felt Lap Ventilator G630. The Manthorpe G630 Felt Lap Vent is designed to be fitted retrospectively to existing lofts to increase the amount of ventilation into existing roof spaces. The product can be easily installed by one person in joist openings from 400mm to 600mm wide to provide 3,000mm² of airflow per unit.
eBay
Garden Furniture Cover with Air Vent Waterproof Windproof Anti-UV Heavy Duty Rip Proof 600D Oxford Patio Garden Table Cover Pack
Aliexpress UK
The product can be easily installed by one person in joist openings from 400mm to 600mm wide to provide 3,000mm² of airflow per unit. The Manthorpe G630 Felt Lap Vent is designed to be fitted retrospectively to existing lofts to increase the amount of ventilation into existing roof spaces.
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Outsunny 6 x 5ft Garden Shed, Plastic Shed with Floor, Window, Lockable Doors and Vents, Light Grey
Aliexpress UK
For cold and warm roof application.
eBay
#For 8 x 10FT Storage Shed with Thickened Galvanized Steel, Outdoor Storage Shed with Lockable Door & Air Vents, Garden Tool&
Aliexpress UK
So you are getting what we state. Not a wild claim, Try a search on Google and see for your self. One of the easiest to use & high quality products on the market. Breathable BBA approved! This felt is being sold 50% less then the RRP!
eBay
Outdoor Storage Shed,Plastic Garden Shed with Windows and Air Vents,Outdoor Resin Tool Shed with Latch Doors,Light Grey
Aliexpress UK