Built-in Protected Circuit: Yes; Auto Circuit Detection: Yes; Over Voltage Protection: Yes; Short-Circuit Protection: Yes; Over-Charging Protection: Yes; Over-Discharging Protection: Yes; Green design of switch its lifetime is longer than others; Comes with power cord easier to reach the power outlets it improved the safety; Built-in protective circuit module it will be safer and made of high quality material which is high-temperature resistant and fire proof; one 5V / 2.1A interface one 5V / 1A interface two 5V / 0.5-1A interfaces it can charge for Mobile phone Tablet PC Portable power Digital camera etc..