Heat and reheat foods with the convenience of a built-in steam vent using Lock n Lock Purely Better 17 oz Vented Glass Food Storage Containers. Featuring a unique 4 hinge locking system for freshness that lasts longer, Lock n Lock Purely Better storage containers are constructed from borosilicate glass, which can withstand both high heat and sudden cooling but are 10 percent lighter than tempered glass for easy, on the go use. The airtight and leak-proof lid has been durability tested to last up to 3 million uses, and features an innovative steam vent to prevent pressure build up when foods are heating or reheating. Plus, Lock n Lock Purely Better glass containers are microwave, freezer, oven, and dishwasher safe. Lock n Lock Purely Better containers are also stain and odor resistant, easy to clean, and come with a Lifetime Limited Warranty for healthy, happy, no worries food storage. Lock in airtight and leak-proof performance with freshness that lasts with the Lock n Lock Purely Better 17 oz Vented Food Storage Container Set.