Lifeguard Aquatics Ultraviolet Sterilizers produce U.V. light at 2537 angstroms, exerting a lethal effect on the unwanted, disease causing micro-organisms. Lifegard Aquatics U.V. sterilizers, when used properly, are extremely beneficial in destroying disease causing pathogens, harmful bacteria, mold spores, yeast, virus, protozoa, fungi as well as algae. Lifegard Aquatics U.V. sterilizers use pure, hard quartz material in their bulbs, which dramatically increases the U.V. output as compared to other conventional bulbs of equal wattage. Pure quartz material resists solarization and improves the longevity of the U.V. bulb. The unique test tube like, pure quartz sleeve isolates the bulb from water contact, providing an optimal bulb operating temperature of 100° f (38° c). This optimal bulb temperature results in a 35% higher U.V. output over conventional units without sleeves.