These Purist Thermal bottles have 2 layer walls to help keep liquids cool. This 26oz design is modeled after a fish tank. Moflow top.

The all-new Purist Insulated features our Chromatek™ liner—a proprietary insulating barrier that lines the core to keep your liquids cold. Not only do your liquids stay cold, but new squeezable materials allow for unmatched flexibility, too.

The Purist Insulated Chromatek™ bottles still feature an amorphous silicon dioxide coating that's infused into the inner-wall of the bottle. Essentially, this forms a glass-like finish that provides a totally natural, and completely inert, solution to the problem of your drinks staining the bottle or leaving behind any residual aftertaste. This infusion also shields your fresh water from tasting like plastic on very hot days, making it akin to drinking straight from a sparkling clean glass.