The Solatube range of tubular daylight systems is explained in a 16-page brochure from Solalighting. These daylight systems use a Fresnel lens on the roof to maximise the amount of light collected and passed down reflective tubing that loses only 0.3% of the light on each reflection. There is a choice of diffusers for the interior space. Compared with systems that use flexible ducting, Solatube is said to deliver, on average, 10 times more light. They are also available with an integral ventilation kit and electric lighting.