WAM Oil uses 100% refined strain specific CO2 cannabis oil in our cartridges. What is CO2 Extraction? Carbon dioxide (CO2) is a supercritical fluid, meaning it converts into a liquid form when pressurized. At the same time, it is a pure chemical substance that occurs naturally and leaves behind no residues. Accordingly, the Supercritical CO2 fluid extraction method can help ensure cannabis concentrates are pure, unaltered, and consistent. CO2 extraction is the cleanest, safest method for extracting cannabis. Which makes it a good option for anyone in search of a natural form of cannabis oil.