To dispense sparkling water, a CO₂ cylinder must be attached to the CUBE. One cylinder provides 60 litres of sparkling water. CO₂ cylinders can only be purchased as a set of four. Empty CO₂ cylinders remain the property of Quooker and must be returned as a complete set of four. Returned cylinders are refilled and reused to make the process as sustainable as possible. Each set helps save 160+ plastic bottles by using sustainable, reusable canisters. Free up storage space, and avoid carrying bottles from the store. Make delicious fruit-infused waters, lemonades, and cocktails. Easy to replace in 1 minute