The 602810-103 Lamp/ Quartz Sleeve Combo Pack by Viqua includes one replacement UV lamp, one replacement UV quartz sleeve, and replacement o-rings. The lamp and quartz sleeve are replacements for the IHS22-E4 system. The quartz sleeve protects the UV lamp from being in contact with your water and from the build-up of film that covers the sleeve with time and usage. 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 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 650733R-001) and sensors can be installed to measure light given off to monitor status and alert you when it is time for a replacement. Enjoy the continuing clarity of your water by investing in the 602810-103 Lamp/ Quartz Sleeve Combo Pack by Viqua today!