HYT Mart 30000mAh Solar Power Bank Backup Battery Charger for GPS PDA Mobile Phone, Red Built-in 30000mAh high capacity rechargeable Li-Ion battery. 30000mAh capability, powerful with long operation time. High efficiency of power conversion. With LED power indicator. Press to charge and press it again stop charging.practical and long cycle life. The Solar Charge is a compact and lightweight solar charger designed for people on the move.