Microwave,Safe Lunch Box Set: 2.9L Insulated Jar With 4 Stackable Containers Convenient Carry Strap

DOUBLE LAYER VACUUM INSULATION TECHNOLOGY: With double layer vacuum insulation technology, it can realize long lasting insulation effect. For better results, please pour hot or cold water into the food jar to preheat or pre cool it for 1-2 minutes before putting in the food. MULTI FUNCTION DESIGN: This insulated food jar comes with 4 boxes to carry a variety of soups or dishes so you can enjoy a richer, more nutritious lunch or dinner.