BRANDS TESTED: Contigo, Hydroflask Standard Mouth and Sport, Yeti, Brita, Aquatix, Bubba Flo, Under Armour, Hydrology, Coleman, Klean Kantine, ThermoFlask, Stanley Classic and East Rim. Thermos bottles tested for cold and hot beverage performance and durability by dropping them 36 inches. Finally, some of the bottles were cut open to look at the internal construction. Several others are durability tested using the Farmabago.