The S810-QL Lamp/ Quartz Sleeve Combo Pack by Viqua includes one replacement UV lamp and one replacement UV quartz sleeve. This offer includes the lamp and quartz sleeve replacement for the S8Q-PA system. The quartz sleeve protects the UV lamp from being in contact with your water and from build up of small matter in water with use. The sleeve should be cleaned about every three months to ensure that the system continues to operate at full efficiency, when the sleeve can no longer be cleaned of the material film that develops with use it must be replaced. The lamp itself has an average filter life of approximately twelve months, depending on your system various controllers (with this system the BA-ICE-S Viqua UV Disinfection System Controller) and sensors can be installed to measure light given off to monitor status and alert you when it it time for a replacement. Enjoy the continuing clarity of your water by investing in the S810-QL Lamp/ Quartz Sleeve Combo Pack by Viqua today!