Description: - The TheDophin 9500 dual air pumps are great for use with air stones to oxygenate and circulate water, enhancing the growth of your plants. Oxygen is a critical part of the hydroponic system as it promotes the stimulation of beneficial aerobic organisms, increasing water quality and aiding in nutrient absorption. Features: - Air control button to increase/decrease air flow 240 liters/hour Safe and quiet operation Dual outlet - Operate two air chambers with one pump Specifications: - Power 3.1 watts Low pressure > 0.1 / High > 0.02 megapascals Output 240 liters/hour