SMART STORAGE: Get lasting freshness, easy cleaning convenience and lasting durability with the LocknLock Purely Better 17-Ounce Vented Glass Food Storage Container. DURABLE: Unique 4-hinge locking system is durability tested for long-lasting performance up to 3 million uses NO MESS, STAYS FRESH: Enhanced locking system is airtight to keep foods fresh longer and leakproof to prevent unwanted drips and spills NO PRESSURE: Innovative steam vent is built into lid to prevent pressure build-up when foods are heating or reheating ULTIMATE CONVENIENCE: Oven safe to 750 degrees F, freezer safe, microwave safe and dishwasher safe for convenience and versatility TEMPERATURE SAFE: Borosilicate glass construction withstands sudden heat and cooling changes up to 250 degrees F