Used a few times, and stored after washing immediately after each use. There are no noticeable stains! If you have any concerns other than what is shown in the photos, please comment, and I will add more photos! Please understand that this is a used item before purchasing. The following is a reference to the description of the same lunch box found on Amazon. *I couldn't find the chopsticks case, but it's a product from the same series. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Material: Silicone, ABS Brand: Afternoon Tea Pattern: Solid Shape: Two-tier, Slim Materials: Surface Coating: Urethane coating Top Lid/Body: PET, ABS resin Inner Lid: Polyethylene Gasket/Belt: Silicone rubber Antibacterial coating on the inside of the body/Inorganic antibacterial agent Size: Capacity: Upper tier 400 ml, Lower tier 220 ml Width: 17.2 cm, Depth: 7.6 cm, Height: 9 cm Product Notes: Heat Resistance: (Top Lid, Body) 140°C, (Inner Lid) 70°C Cold Resistance: -20°C Antibacterial treatment does not work against all bacteria. Since it is not a sealed container, water may leak. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~