Using your Hydro Flask 28 oz. All Around™ Tumbler is easy. First, open the Closeable Press - In Lid by sliding it open wide. You can pour your hot or cold drink into the tumbler. If it's a hot drink, close the lid tightly to keep it hot for up to 6 hours, and for cold drinks, it'll stay cold for up to 24 hours. You can even use a reusable straw as the lid opens wide enough. The tumbler has a tapered design, so it's really comfortable to hold in your hand and fits well in most cup holders. When it comes to cleaning, you can safely put it in the dishwasher thanks to the Color Last™ powder coat. This coat also gives it a non - slip feel. Just remember, since it's made of 18/8 pro - grade stainless steel, it's very durable and won't transfer flavors. And it's BPA - Free and Toxin - Free, so you don't have to worry about any harmful substances. Keep it clean and it'll serve you well for a long time.