1. [4-piece set&safety silicone material]: 4-piece set of foldable food storage container contains 2 square boxes (350ml and 500ml) and 2 round boxes (350ml and 500ml), which can meet different food storage requirements. In addition, each container is made of high-quality BPA-free food-grade silica gel, which is soft, non-fragile and non-toxic. 2. [Airtight storage and space saving]: The buckle and exhaust valve create a closed space to prevent dust and keep food fresh for a long time. In addition, these foldable food storage containers are also foldable, easy to store, and can be folded to save about 50% of the space. 3. [Microwave, refrigerator and dishwasher safety]: dishwasher, refrigerator and microwave oven safety. The temperature tolerance of the remaining containers is about - 4 F to 428 F/- 20 C to 220 C. Tip: Before heating, pull up the vent valve on the cover or remove the plug!!! 4. [Purpose]: 4 bags of foldable food preparation containers, including square and round containers, small (350ml) and medium (500ml) size, can adapt to various conditions. For example, store grains, fruits, vegetables and leftovers in the refrigerator. In addition, it can also be used as a lunch box for office staff. In addition, if you are traveling or camping, it helps to carry food easily.