50dB low noise oxygen pump. Suitable for outdoor aquarium, pond or fishing. Solar powered oxygen pump, no battery or plug required, economical and environmentally friendly. Comes with 2 soft hoses, 2 air stones and a connector. Built in a 3.7V 1800mAh 18650 lithium battery to store energy, thus the oxygen pump working in the night as well. Easy to dual airflow with the included [Y] connector. 50dB low noise oxygen pump. Suitable for outdoor aquarium, pond or fishing.