Home Puff brings to you Double Wall Vacuum Insulation technology lunch box, which provides maximum temperature retention of heat or cold. It keeps contents hot for up to 5 hours or cold for up to 9 hours. All credit goes to the durable vacuum insulation and double wall stainless steel construction, this food jar remains cool with touch of warm foods and sweat-proof with cold foods. It is made from BPA-free material and durable stainless steel interior food grade material. The wide mouth opening is easy to fill, eat from and clean. The compact and insulated stainless steel lid doubles as a convenient built-in serving bowl.