BPA-FREE; DISHWASHER SAFE; MICROWAVE SAFE; SEALABLE; STACKABLE; REUSABLE. FOOD-SAFE MATERIAL: To ensure safety and health, we are surely serious about the choice of materials. The plastic of the container body is high-quality food-grade plastic that is impeccable, and it is more durable and sturdier that is thicker than others to keep that they would be used for a longer time. Besides, they are totally BPA Free, phthalate free and lead free. EXCELLENT AIRTIGHT SEALING & STACKABLE: The lids of the salad dressing containers are super air tight so that the food inside can keep really fresh and clean, and avoids to be polluted or spoiled. And airtight also means leak-proof that if carried outside, you do not need to always pay attention to whether food is spilled or leaked. And the design of the lid makes them stackable to get easily distinguish and space-saving storage. SAFE FOR FRIDGE & MICROWAVE OVEN & DISHWASHER: To store, the condiment containers can be put in the refrigerator,