Viqua LAMP/QUARTZ SLEEVE COMBO KIT FOR...Viqua IHS22-E4E/E PLUS, E4/E4 PLUS, PRO7 BY VIQUAUV-Max Lamp/Quartz Sleeve Combo Kit for E/E PLUS, E4/E4 PLUS, PRO7 by ViquaUV-Max Lamp/Quartz Sleeve Combo Kit for E/E PLUS, E4/E4 PLUS, PRO7 by ViquaProduct OverviewFeatures:UV Max lamps install with an easy quarter-turn to a positive stop to prevent over tighteningLamps should be replaced after one year of operation to ensure proper disinfection.Each replacement lamp is shipped with complete installation instructions with images.Replacement Lamp includes 2 O-rings.UV Lamp:All UV Max systems include an ultraviolet lamp, which is surrounded by a quartz sleeve. The amount of UV light created by the UV lamp decreases over time, requiring that the UV lamp be replaced.