LUX 8100 is Retractable insect screen that helps to prevent the annoying mosquito and flies whilst keep your home well-ventilated at the same time, even without sacrificing your desire for wonderful outdoor scenery view. After several improvements made, Retractable unit has better quality in the sound and motion aspect now. The insect screen has smoother and quitter rolling with the Adjustable Spring and the combination technology of Spring Mechanism and Hydraulic Barrel.