BestDevice Safer Hammer Dual USB Car Charger 3.1A with Escape Emergency Safety Hammer Function UNIQUE HAMMER DESIGN: The Special Stainless Steel Tip Can Be Used In Emergency Condition To Protect Your Family And Yourself Dual USB ports,total max output 3.1A, charging 2 devices simultaneously. You can charge smartphones, tablets, music players, and electronic devices on the trip. Reliable and Safe: with protections against overheating, overcurrent, and overcharging. Charging will stop automatically when battery is fully charged.