How do I choose a water cooler for my Gravity Water System Dispenser model?

There are plenty of compatible water cooler units on the market. They need to fit the following qualifications:

• The water cooler must have a removable bottle collar. The bottle collar is the plastic collar that sits inside the reservoir. Most dispensers have removable bottle collars. 

• The water cooler must also have a flat top and at least 6 inches of void space within the tank to allow for movement of the Gravity Water System's float valve.