Our most popular size, the 27oz Klean Kanteen Classic is perfect for your on-the-go life. Whether you're trying to juggle a full day of classes or work, the kids' extracurricular schedules, or a trip to dog park between your workout and happy hour, just one or two fill-ups will help you stay hydrated and happy all day. The bottle is made from high quality, 18/8, food-grade stainless steel that's totally free of BPA and other toxins. Because stainless steel itself is safe, we don't need to coat the inside of the bottle with a plastic or epoxy lining, which is one of the main differences between a stainless steel Klean Kanteen and aluminum bottles. Food-grade stainless steel is used in the brewing, food and winemaking industries too. It's the material of choice because it doesn't retain or impart flavors. No matter how many times you refill it, no matter what you put into it, your 27oz Klean Kanteen Classic will keep your drinks fresh, crisp and clean tasting. Plus it weighs only 6 ounces and is durable and designed to last for years. All our caps are BPA-free too. The 27oz Classic also comes with the new and improved Sport Cap 3.0 that's six times stronger and more impact resistant. The large-mouth design allows you to pour in big stuff like ice cubes, and makes cleaning your Klean Kanteen Classic as simple as scrubbing it out or throwing it in the dishwasher. Yet the slim design fits into most cup holders and the the Kanteen Bike Cage.