HITOP Aquarium Air Pump with Accessories, Adjustable Aquarium oxygen Pump, Silent Aquarium Aerator for Fish Tank 30L to 400 L. [Ultra-Quiet] This air pump adopts the latest technology to make it ultra-quiet in working, Minimum 40dB, just sound like rusting leaves or ticking watch; Moreover, we use an extra thickened shell to wrap the joints of the body of the air pump, to eliminate the noise further.
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