1. Designed for Surface Laptop (2017) & Surface Pro,compatible with Surface Book / Surface Pro3 / Surface Pro4 / Pro5 / Pro6 | 2. Input: AC 100-240V Output: 15V 2.58A 44W. USB Port: 5V 1.5A | 3. 44W Power Supply quickly recharges the battery and the USB port allows you to charge another device such as your phone at the same time. | 4. PROTECT: with premium ABS+PC fireproof materials and built-in IC chip technology provide overcharge protection system/ short-circuit/overload protection/Over-heat protection. | 5. All products must undergo a 48 hour aging test and validated; Our products are UL, FCC, RoHS certified for safety.