About this product 【Safe Materials】The inner liner of the hot water bag uses safe and soft PVC material. The outer material uses imitation rabbit fur, which is gentle on the skin and has a soft texture. There is no need to use electricity, so there is no risk of fire. Please let us experience a warm winter. 【Long-term Heat Retention】By using thick PVC material combined with the outer cloth cover, heat is transmitted evenly through physical conduction, allowing for long-term heat retention. When used indoors with hot water, the warmth lasts for 3 to 6 hours, and in a futon, it lasts for 8 to 12 hours. 【Leak-Proof Hot Water Bottle】You can use it with peace of mind by simply screwing the lid to seal the hot water bottle, and you don't have to worry about the hot water leaking from inside. It is suitable for hot water and ice water, is leak-proof, and can be used regardless of the season. The cover is made of a soft material that makes you feel warm. 【Applicable Range】The hot water bottle can warm the whole body and relieve muscle pain, stiff shoulders, lower back pain, menstrual pain, arthritis, stress, and cramps. You can also add ice water and use it as a cold compress to reduce swelling from minor injuries.