Screw a universal ” threaded CO2 Cylinder not included into the regulator to carbonate your beverages. One 16g CO2 Cylinder is suitable for up to 128oz beer before it needs to be replaced. Slim design with vacuum insulated double-wall no matter with or without the tap systemmeans perfect storage for any homebrew or other craft beverage to stay fresh for up to 1 week. Dial the CO2 regulator slowly to check the CO2 Cylinder is active at more than 0 psi. normally turning on 3-5 psi is enough to get the beverages carbonated Stock up on your favorite beverages so you can toast with your favorite beer cocktail or soda with loved ones by your side anytime.