TLF 14" (35cm)diameter flexible tunnel. Exterior flat glass window appearance. Easy to clean coating keeps glass cleaner for longer. Easy to install with integral flashing to suit slate up to 8mm thick. Double layer ceiling diffuser with new Edge-Glow technology increases the spread of light. Can be used for night time lighting with an optional low energy light kit (ZTL 014). Flexible sun tunnels are recommended for tunnel lengths of 0.4m to 1.5m (2m supplied)in cases where a rigid installation would be more difficult due to an obstacle in the loft space. Extensions are not available for this product. Suitable for roof pitches 15-60°