Simply push the lid down to secure it.

When shopping for a tumbler, there are many factors to consider. The first thing you should think about is the material it's made of. Stainless steel is durable and great for keeping drinks hot or cold for a long time. Glass is fragile but can be an option. Plastic is cheap and lightweight but not as effective at insulation. If you want a tumbler that can keep your drinks hot or cold for hours, look for one with good insulation. Double-wall insulation is common in tumblers and can help keep drinks at the desired temperature for longer. Next, consider how much liquid you want your tumbler to hold. Tumblers are available in sizes from 8 ounces to 30 ounces or more. The type of lid on your tumbler is important. Look for a lid that seals tightly to prevent spills and leaks. Some lids also come with a straw, which can be useful for sipping cold drinks. Next, make sure the tumbler you choose is easy to clean. Look for a dishwasher-safe design or a wide mouth that makes it easy to clean by hand. Tumblers come in various designs, including plain, colored, and patterned. Choose a design that fits your style. Finally, consider the reputation of the brand you are buying from. Look for a company with a history of producing high-quality tumblers that last. Considering these factors, you can choose a tumbler that meets your needs and provides you with years of use.