Unique fastener reduces the amount of germs that could contaminate your water. Adjustable n bendable tubes system helps pump to adapt to each size and also allows you to completely empty the bottle.With the combination of BPA less food grade plastic materials, its soft/gentle press system is comfy even for elders and kids to get safe drinking water from bubble-top cansAdjustable neck settings allows it to fit onto standard 20l water cans making it easy to assemble and quick to be cleaned