They're easy to open and close thanks to Grip n Seal technology, which also helps to lock out freezer burn and lock in freshness so the food and treats you store taste great! Great for handy freezer storage, while they're also safe to use in the microwave and are BPA free. Ziploc brand Freezer Bags are the ideal size for storing sauces, soups, stews, meals and leftovers, as well as for keeping bulk ingredients conveniently separated. For up to 12 weeks protection of your food.