Price history on Walmart.com for
Pentek CBU-10 Carbon Block Filter Cartridge for UV Systems 9-1/2 inch x 2-3/4 inch 0.5 Micron
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Pre-filter for the UVS-110 and UV-110 ultraviolet systems Maximizes transmittance of IV light through the water The PENTEK-CBU-10 carbon block filter cartridge surrounds the quartz tube and acts as a prefilter to maximize transmittance of UV light through the water and reduces cysts. The CBU-10 is an ideal prefilter for use with the UVS-110 and UV-110 ultraviolet systems.
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