The VELUX Rigid Sun Tunnel is used to introduce light into naturally dark areas with no windows such as bathrooms, corridors and cupboards. The sun tunnel comes with a Clear and Clean coating which keeps the glass cleaner for longer. This sun tunnel is suitable for tiles up to 120mm and has a diameter of 14. It also features a super reflective coating along the interior of the tunnel which provides a 98% internal reflection rate. Rigid sun tunnels are recommended for maximum daylight and are easy to install with their integrated flashing. An easy to assemble diffuser kit comes complete with a frosted acrylic insulating pane and a standard, white ceiling trim ring too. Can be used for night time lighting with an optional low energy kit and rigid extensions are available for deeper roof structures. Suitable for roof pitches between 15 - 60 degrees. The sun tunnel comes with the VELUX 10 year guarantee.