Includes: CO2 Regulator with Needle Valve 1.0L CO2 Bottle CO2 Bottle Supporting Base Airline Tubing CO2 Tube Holder 3-in-1 CO2 Diffuser (M) CO2 Indicator Solution for CO2 Indicator Features: TUV safety regulation approved aluminum CO2 bottle that is durable and safe Supporting base to prevent damage to CO2 regulator or bottle from tip-overs CO2 regulator features a pressure-reduced design to provide stable and reliable output 3-in-1 CO2 Diffuser includes bubble counter, check valve and diffuser. Easy to install, efficient and easy to replace ceremic diffuser discs. Convenient CO2 tube holder to hold tubing in place. CO2 Indicator provides coninuous and accurate monitoring of the CO2 level.