Some of the product photos can be a bit confusing, so the question is understandable.
Each 6 pack kit is a full case of spray cartridges. This includes (6) dual cartridges. Each cartridge has two 750 ml containers for a total of 1.5 liters per cartridge.
With each case, you get 9 liters (2.37755 gallons) of material.
We should probably post a new picture to show all 6 cartridges in order to avoid confusion.
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