Stanley flasks have survived speeding bullets, 4000ft drops, -70° windchills, Category 5 hurricanes... anyway, they're serious when they call them “unbreakable.” A great gift for the would-be adventurer. This one is made of stainless steel that's leakproof, dishwasher-safe, and BPA-free, with a handy, wide mouth that's easy to fill (no funnel needed) and a machined steel captive-top cap that's impossible to lose. Please check your local open-container laws before going crazy.