1 Air Stone Ball: 2 D x 3.4 H(cm). Steady Output: Max air flow rate: 1.8 L/ min (30 GPH); Pressure: 0.012 MPa; Power: 2 W. Quiet Aeration: With diaphragms inside and 4 shockproof rubber feet to reduce noise and vibration, the pump gives out noise less than 45 dB like the hum of a refrigerator.
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