3 Powerful batteries – This Power bank kit comes with 3 ultra-thin powerful rechargeable lithium polymers, 5V USB for continuous use. LED INDICATOR LIGHTS – This portable power bank 5V is designed with LED indicators that display battery life and charging status. The charging time for the power bank is 3 to 4 hours. COMPATIBILITY – This 5V power bank kit is compatible with your 5V heated gloves, glove liners, socks, balaclava, or hats to provide all-day warmth in cold weather conditions.