Soda Buddy SB4OZCO2 CO2 Refill Cylinder - 16 Liter Capacity Keep your soda machine pumping bubbly goodness, with the Soda Buddy CO2 Refill bottle The Soda Buddy CO2 cylinder fits most Sodastream machines of any size 1 x 4 oz. CO2 Bottle; Can fill approximately 16 One liter Soda Bottles, depending on usage and carbonation strength