Polar Thermal Insulated Bottle - 20oz., 2014 Commemorative USA Pro Challenge Water Bottle Double-wall construction: a thermal barrier of air keeps heat out and cold in. Polar Bottles do not contain Bisphenol-A (BP-A), a potentially toxic compound. Fits standard bicycle water bottle cages Wide mouth allows ice cubes easily into the bottle and makes cleaning easy. Dishwasher and freezer safe.