Thermal Insulation: The bento box uses high-grade 18/8 stainless steel construction with double wall vacuum insulation to keep food hot or cold for hours without losing temperature. Portable Design: Lightweight and compact at only 5 inches long, this bento box easily fits in most bags and backpacks to take your home-cooked meals on the go. Leakproof Security: The airtight locking lid provides leakproof protection to prevent spills while transporting soups or other liquids anywhere. Versatile Compatibility: Suitable for use in the microwave, oven, freezer, and induction cooker for flexible re-heating or storage without risk of damage.