Trojan UVMAX 3A UV Quartz Sleeve: Replacement Sleeve for Trojan UVMAX 3A systems. Sleeves must be wiped clean regularly. Replace sleeve if fouled or damaged.Specs Finish kind: Domed ID: 0.71″ or 18mm ± .2mm OD: 0.81″ or 20.5mm ± .2mm Duration: 11.46″ or 291mm ± 3.5mm Genuine Viqua quartz sleeve for a Trojan UVMax 3A model systems. The UV Max 602730 Quartz sleeve supplies thermal protection for the system UV lamp and protects it from conceivable water harm.