[Size] --17*28cm [Professional Material] -- Thermoplastic material which is odorless and recyclable. This kind of thermoplastic material can hold heat longer than a traditional hot water bottle. Could be used as an ice pack, or cold water bottle. Note, this is not suitable for Microwave oven heating. [Safe & Easy to Use] -- The hot water bag is explosion-proof, leak-proof which is good for daily use. Pregnant women and children can use it safely since it is odorless. Please fill only two-thirds 80 degree water into it. [Product Highlights] -- The product can retain heat for an extra long time. Ribbed outer surface helps maintain liquid temperature. [Best Assistant] -- This hot water bottle can ease joint disease, sore muscles, cold and cough, dysmenorrhea and other common aches.It can also be a cold compress for people with fever or to reduce swelling for minor injuries.