Not easy to leak: Spill-proof caps for standard (55mm) 2.3, 5 and 6 gallon bottles, not for use with screw cap bottles. Easy to use : Only the diameter of the water bottle is 55mm and frictionless, then press hard until you hear a "pop" sound. This is the important step to prevent leakage. Sealing: Leak-proof inner cover + sealing cover, can ensure a sterile environment and spill protection. Make sure you can drink clean water. Reusable: Replace many times, say no to a lot of unnecessary disposable water caps, save resources and protect the environment. Suitable for many occasions: as a water dispenser, bottle with pressure cap, water cooler, water carafe on the top basket, water bottle pump, filter pump with water pump . The waterproof inner lid does not float in water and can prevent spills.