1. Input: 100-240V 50/60 Hz (Universal); Output: 15V-2.58A 44W; USB port 5V-1A 5W. It works with surface pro 15V-2.58A 44W and 12V-2.58A 36W. | 2. Compatible Models: Surface Book 1 & 2, Surface Laptop ,Surface Pro 6, Surface Pro 5, Surface Pro 4 Tablet, Surface Pro 3 Tablet. | 3. With additional USB 2.0 charging port of 5V / 1A. You can charge another device such as a phone at the same time. | 4. Built-in IC chip technology provides overload / short circuit protection / overload protection / heat protection. We test each charger to ensure a tight, strong magnetic connection. | 5. Warranty: 12-month limited warranty , 30-day money back guarantee. Contact us and we will get back to you within 12 hours! Our goal is to provide you with a safe and reliable surface adapter.