The ISTA CO2 Aluminum Supply Set 1L (Advance) is a complete CO2 system including a full CO2 cylinder (1 L), supporting base, pressure regulator, diffuser, air pipe, CO2 indicator w/ solution and CO2 pipe holder. The ISTA CO2 cylinder safety standards are approved by the Technical Inspection Association. The supporting base keeps CO2 cylinder in position avoiding any potential damage to the CO2 regulator. The regulator provides a constant and reliable CO2 dosing rate, and the 3 in 1 CO2 diffuser provides clear CO2 bubble readings and quality diffusion. The stainless spring-design check valve prevents backflow.