[Health & Pain Relief]: Works only when plugged in, no battery option; The back electric heat belt is made of graphene, softer and healthier; Electric heating belts provide comfortable warmth for back pain, alleviate muscle soreness , relieve cramps, sedentary lifestyle and keep waist warm; Perfectly suitable for women, the elderly, office workers, etc [Fast Heating & Dual Compression Straps]: Plug & play and heat up in seconds, the USB heating belt works when plugged into the power source, and the low current is safer for using; Two adjustment straps provide custom fit and compression, making the electric heating belt lock in place where you need it [Portable with pocket to insert power bank]: The electric back warmer is equipped with a pocket, which can hold a medium-thin power bank (n.
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