Welcome to our store! SIMPLE ONE-BUTTON OPERATION: One button to pump water; press once to pump, press again to stop. Press the button twice, and it will automatically stop when the water volume reaches 600ml. Convenient and fast, even children and the elderly can use it easily. EASY INSTALLATION AND PORTABLE: This portable water bottle pump is compact and easy to carry. Installation is simple; just place it on top, and it's ready to use. This is a fantastic alternative to a bulky, large 5-gallon water cooler. HIGH COMPATIBILITY: This drinking water pump is suitable for pure bottled drinking water and compatible with most 3L-18.9L bottles. For the pump to better grip the neck, do not pry open the lid of the water bottle. The water bottle cooler is suitable for gallon barrels with a 2.16-inch (5.5 cm) neck. Please confirm the size of your neck before purchasing. USB RECHARGEABLE: This water jug pump has a high-capacity rechargeable battery inside, which is quite impressive for a device like this. It can be used for 30-50 days or about 4-6 bottles of 5-gallon water when fully charged. For a small family, it only needs to be charged once a month. Satisfaction: Our customers are our top priority. If you find any problems with the product after receiving it, such as damage or an incorrect quantity of goods, please contact the seller immediately. We will do our best to provide you with satisfactory customer service.