It's made of stainless steel internally with plastic outer which keeps your food warm or cold for 2-3 hours, also keeps fresh and protects against spoilage. Our ergonomic handle makes it easy to carry your food with you, namely hassle- free. It is convenient for you to take your meals when you go to school, camping, picnic or any outdoor activities. You can choose 1/2/3/4 layers, since layer design can separate out the food among defferent layers and keep food delicious. Go with endless color possibilities and put your brand on something that's built to our stainless steel insulated lunch box set. Price over 5,00 pcs is via sea shipment.