The VIQUA QS-012 is the protective quartz sleeve and S740RL-4C is the UV lamp in the VIQUA SHF-140 series of UV systems.
ANNUAL LAMP CHANGE: After a year, UV light weakens and isn't strong enough to properly treat your water. Replacing your lamp annually with a genuine VIQUA lamp ensures optimal system performance.
For use with VIQUA SHF-140 and SHFM-140 UV systems.
R-Can Sterilight Ultraviolet Sterilization Systems. Replacement Quartz Sleeve Model Number of Quartz Sleeve: QS-012. Description: Replacement Quartz Sleeve Replacement for UV System Models: S12Q-PA, S12Q, S12Q-GO.