Some Cirkul SIP flavors have sodium while others do not. The last posted nutritional guides show that LifeSIP, TeaSIP, BrewSIP and PureSIP flavors do not have sodium. However, GoSip and FitSIP flavors have 10mg and 50mg of sodium respectively.
When in doubt please read the nutritional guide that comes with the Cirkul SIP flavor cartridges.
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Cirkul
A water bottle that customizes the flavor of your water