USB Rechargeable: Rechargeable battery provides up to 30hrs working time. Compared to other battery aquarium air pumps, this kind of rechargeable function free you from replace the battery, you can charge it with a laptop, a wall charger, or a power bank, save your money and eco-friendly. You can take it for outdoor fishing, fish transportation and power outages, etc. Powerful Motor & 2 Air Outlets: Small air pump, but equipped with powerful power can generate a large amount of aeration, Max Flow Rate: [2.5L/minĂ—2]. Put out a ton of air bubbles via 2 air outlets and provides a sufficient amount of water circulation in your aquarium. Wide Compatibility: This quiet air pump is perfect for both Freshwater and Marine Aquariums, great to be used for all types of tanks with capacity of 19-113L(5-30gal). Excellent emergency aquarium oxygen pump! Safe & Energy-Saving: With 2 check valves to keep water from back flowing into your pump, much safer. with rated power of 4W, this air pump is