【Microwave oven Available】It could be heated by microwave oven. Please fill it 80% capacity in cold water, and the heating time is 2-3 minutes. Attention that heating power should be not over 1500W. 【High Quality】 It is easy to fill up water with wide mouth. The hot water bottle can maintain temperature 4-8 hours. it also could be put into refrigerator to get a ice bag. One-piece molding process, good sealing, explosion-proof and water-proof. 【Excellent Material】The hot water bottle is made of food grade silicone, odorless and recyclable, which is Non-BPA. Each hot water bag is 0.54lb, 3.2in * 3.4in*8.3in.