Ozone vacuum-ultraviolet (VUV) ozone generators, employ a light source that generates a narrow-band ultraviolet light, a subset of that produced by the Sun. The Sun's UV sustains the ozone layer in the stratosphere of Earth. UV ozone generators use ambient air for ozone production, no air prep systems are used (air dryer or oxygen concentrator), therefore these generators tend to be less expensive. However UV ozone generators usually produce ozone with a concentration of about 0.5% or lower which limits the potential ozone production rate. Another disadvantage of this method is that it requires the ambient air (oxygen) to be exposed
Stratosphere: Conquest of the Skies and can be fired at wanted direction after clicking on position that is in its firing range. Some turrets can also shoot at ground level, which is used during missions in the campaign to destroy turrets placed on the ground. Stratosphere: Conquest of the Skies Stratosphere: Conquest of the Skies is a Vehicular combat game and also a real-time strategy PC game, developed by Kodiak Interactive and published by Ripcord Games in 1998. Stratosphere focuses on floating island battles which players control. Gameplay consist of the player controlling a single floating island which are called flying fortresses in the game.