Alfred Hydroponic Air Pumps are the perfect choice for providing fresh oxygen to your hydroponic growing system. Good aeration is absolutely necessary as it promotes nutrient uptake and aids in the growth of beneficial organisms. Aerating the nutrient reservoir will also help maintain a consistent temperature while discouraging the growth of algae, bacteria, and other pathogens. The steady air output pressure can be fine-tuned using the power adjustment knob located on the top of the air pumps’ casing. Other features include vibration absorbing rubber supports, molded ABS casing, low-power consumption, and more. Quiet and reliable, Alfred Hydroponic Air Pumps are designed for hydroponic growers and indoor farmers of all levels and are available in a variety of air pressure levels to match your requirements Features: Steady air pressure, Tunable air flow,Near silent operation, Vibration absorption system, Strong ABS casing ROHS compliant, 1 Year warranty