Lightweight, ruggedized, wide-mouth hip flask Your favorite beverage can now go anywhere in the Boulder Flask. Includes graduations for measuring and can take any fall with the sleek bumper flask. The Boulder 6 Flask holds 6 fl oz, has a shatter-resistant body with bumper, graduations, and a hinged silicone cap making it impossible to misplace. Features: Shatter-resistant, copolyester resin body and grippy, silicone bumper mean this flask can go anywhere. Wide mouth makes for easy filling, pouring and drinking. Hinged top with silicone grip is easy to open and impossible to misplace. Convenient molded graduation marks. Material: Copolyester, Silicone