What materials are the vents and canopies made from?
The trickle vent is a thermoplastic moulding made from a UV stable grade of PBTP (PolyButylene TerePhthalate) and POM (PolyOxyMethylene). This material gives excellent properties in strength and rigidity (with spring like qualities) as well as resistance to wear and organic solvents. The canopy is made from uPVC and like your windows has excellent weathering properties.