Water Bottle Pump, USB Charging Automatic Drinking Water Pump Portable Electric Water Dispenser Water Bottle Switch For Water Dispensers Note: This drinking water pump is suitable for gallon barrels with a 2.16-inch (5.5cm) neck. Operating Voltage: DC 3.7V Power Rating: 3.8W Charging Time: 3-4 Hours Charging: Micro-USB Charging Cable Suitable for: 2,3,4,5 Gallon Water Bottles Size: 2.9*5.1 inch/7.5*13cm Hose Length: 21.7inch Pipe Length: 4.7inch Instructions: Connect the silicone hose and insert the silicone hose to the bottle. Then fasten the water pump Press the button to pump out the water Press the button again to stop pumping Charge with the Micro-USB cable when out of battery colour: Black + white Material: ABS+stainless steel