Long Zoom 1 Lens - LS2LT2\n"To support optimal projector installation and performance in a wide range of environments, seven types of optical lens ranging from short-throw to long-throw lens are available with glass materials for better focus and large apertures for a brighter image. The lenses are made in Japan to ensure the highest quality. Zoom Ratio: 1.67:1 Throw Ratio: 3.11 ~ 5.18 (PX9210) Throw Ratio: 3.0~5.0 (PU9220) Click here to understand more about Professional High Brightness Installation Projectors"