Boulder 10 Flask

The GSI Outdoors Boulder 10 Flask is a lightweight, ruggedized hip flask built for travel and outdoor use. It carries 10 fl oz and uses a shatter-resistant body with a sleek silicone bumper, so it holds up well when it gets knocked around in a pack, camp bin, or glove box.

In practical use, the details are what make it easy to live with. Graduations help with measuring, and the hinged silicone cap stays attached, so there’s no loose lid to lose when you’re pouring a drink at camp. It’s a straightforward flask that travels well, with the one honest tradeoff worth noting: long term storage of liquids may affect flavor.