SMART STORAGE: Get lasting freshness, easy cleaning convenience and lasting durability with the Lock and Lock Purely Better 13-Ounce Round Glass Food Storage Container. DURABLE: Unique, patented 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 ULTIMATE CONVENIENCE: Oven safe to 750 degrees F, freezer safe, and microwave safe for convenience and versatility EASY CLEAN: Dishwasher safe for easy cleanup