Purely Products PUVH2305 5-Watt UV-C Germicidal Ultraviolet Replacement Bulb Non-chemical approach to disinfection; Fits the G23 base, has one molded snap and is 4-Inch in length At least 16,000 microwatt seconds per square centimeter but many units actually have a much higher dosage Commonly found in laboratories, hospitals and clinics to sterilize surgical equipment 8,000 hours or more of normal usage Prevents DNA of germs to reproduce