Preserve everything--even storage space--with Ball Nesting Jars. These Wide Mouth Mason jars have a unique design that allows them to securely nest and stack with each other when not in use, saving 30% more space versus Ball Regular Mouth pint jars. Compatible with other Ball Wide Mouth jars, these 16 oz., BPA-free Nesting Jars are not only canning-safe and can seal for up to 18 months, but they're also ideal for drinkware. They're even shaped to fit perfectly in a cup holder for on-the-go drinkware use.