See more about this article : Emperor Aquatics T5-UV Lamp - 40 watt

The 40 watt Replacement UV Lamp for various aquarium SMART UV Sterilizers, such as the 40 watt SMART UV Lite and the 40 watt SMART UV Sterilizer, is made of high quality quartz glass and offers 13 months (9,000 hours) of continual operation of lamp life. The 40 watt ultraviolet lamp has a length of Length of 33.25" and a diameter of 0.75".

NOTE: All UV Sterilizer gaskets and o-rings must be replaced annually to ensure a watertight seal.