Quartz sleeve for the Hanovia UV1000 disinfection system, 728 mm long. The quartz sleeve is the pressure barrier between the treated water and the lamp, and the only optical path between them, so it must both hold system pressure and pass UV without loss. This catalogue also lists a 728 mm sleeve catalogued against both the UV1000 and the UVS 2.5 under reference 2264-0908; if you are ordering for a UV1000, check both listings against your parts list. The type D O-ring used on the UV1000 is stocked separately. Reference number 2298-1012.