Not like most other cold plunges on our list, which use ice or an exterior chiller, the Solar Household Plunge Pro has an integrated chiller that cools water up to twenty-eight degrees Fahrenheit (the bottom on our list). It is a small issue, but we adore the way it simplifies http://www.digitalizze.com/directory/listingdisplay.aspx?lid=36212#.Y-COGna9thE