Drop the shorty and go with the 40! The Hydro Flask 40 oz Wide Mouth Stainless Steel Water Bottle is made for serious hydration and sustenance portability. Whether you're climbing a mountain with your favorite malt beverage or carrying soup to Grandma's house, the 40 oz water bottle is sure to fill you up! The Wide Mouth features our largest water bottle opening at 2.25 inches. The water bottles were developed to perform in every environment. Each Hydro Flask is cast from double wall vacuum insulated food grade 188 stainless steel, therefore they are BPA Free and resistant to bacteria and odors. The double wall vacuum insulation technology allows Hydro Flasks to keep contents Hot and Cold!