• Ensure a watertight seal between the roof window and the roofing underfelt with the VELUX underfelt collar that leads water away from the roof window installation
• Everything you need in one box for a weathertight installation ? with added insulation
• Suitable for natural slate up to 8 mm thick
• Includes BDX collar which insulates around the roof window frame, reducing heat loss and eliminating cold bridges
• Suitable for roof pitches between 15-90?
• No exterior maintenance is needed ? once installed, VELUX flashing sets are maintenance-free

Also comes with a 10 Year Guarantee