... for MP3,MP4,GPS,e-BOOK and so on. Charging protection Portable power bank(M16)1.Built-in li polymer core/specification ... :6-7 hours7. Cycle life: ≥750 times8. Protection function: Charging protection,discharge protection,short circuit protection,overload protection 9. Be suitable forMP3,MP4,GPS,e ... : -10°C-40°C14. Storaging temperature: -10°C-45°C portable mobile power bank