Replacement ultraviolet lamp for the Hanovia QMB100B/1/4/MHX medium-pressure disinfection system. Medium-pressure UV lamps lose output steadily through life rather than failing outright, so they are replaced on elapsed running hours against the system’s dose record, not when they stop lighting. The matching 360 mm quartz sleeve for this system is stocked separately, and it is normal practice to inspect or renew the sleeve when the lamp is changed, since sleeve fouling and lamp ageing both show up as the same falling UV reading. Reference number 2282-0211.