Safe Material: This BPA free drinking water dispenser is made of food grade silicone hose, 304 stainless steel and high density ABS plastic, non-toxic, odorless. Easy to use: connect the silicone tube dispensed to the bottom of the fuselage, insert the water tube into the water and place the pump on the barrel neck. You just need to press the switch button and fill the glass or bottle, press again to stop working. USB Rechargeable BatteryThis automatic water pump is built with 1200mAh rechargeable lithium battery, it can last for 30-40 days or about 4-6 5 gallon water bottles. You can take it with you when you camp or picnic. High Compatibility: Fits 2.16 inch (5.5cm) neck barrels without lifting the lid. For 3, 4, 5 liters/cans of water bottles. Not for threaded/screwed caps. Please confirm the barrel neck or contact us before purchasing. Quantitative design: two on/off buttons, one for normal use and one for the 600 ml button. Press the 600ml button and the water outlet will automatically turn off after reaching 600ml.