It's this one I picked up from BRS. I still have it and really like it.
DLC4 Quadruple Dosing Reservoir
Save space with the Skimz DLC4 Dosing Reservoir! Holds up to four of your favorite additives. Keep calcium, alkalinity, magnesium, and any other liquid in the four 1.5L dosing containers. Each container includes color-matched tubing and labels allowing you to know exactly what is in each...
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