smart explosion-proof rechargeable large hand warmer electric hot water bag one-piece batch

2026 new model hand warmer: instantly heats in 3 seconds, maintains a constant temperature of 55°C, has a battery life of 12 hours, supports fast USB charging, is safe and explosion-proof, providing warmth for the winter. Featuring graphene heat generation and far-infrared therapy, it relieves cold hands. An essential item for work and home use. Certified with CE/FCC, ensuring quality. Warm hands, improve mood, a comforting little joy in winter.