2 layers of thermal insulation and moisture-proof fabric and 4 layers of high-strength PVC inner film
https://www.lexueer.com/product/rechargeable-hot-water-bag/explosionproof-electric-heater-plush-cute-hand-warmer.html
2 layers of thermal insulation and moisture-proof fabric and 4 layers of high-strength PVC inner film
https://www.lexueer.com/product/rechargeable-hot-water-bag/explosionproof-electric-heater-plush-cute-hand-warmer.html