Lucco 5.5 x 2.1mm Charger Adapter Power Bank Charging Cable Data Cord for Microsoft Surface 3/Pro 3/Pro 4 Tablet Fit powerbank with 5.5 x 2.1mm interface ONLY. If your powerbank is other size, you need an adapter to connect the cable and the bank. Power bank output plug: 5.5 x 2.1mm, input plug: magnetic suction plug for surface pro 3/pro 4. The cable makes from 20 new pure copper wires to avoid getting heat, to protect tablet and user's safe. Cable length: 1.2M. Matte material to protect the plug from being scratched. NOTE: Microsoft Pro3 tablet requires 12V 2.58A to charge. Please do not charge the tablet by using 5V charge, it will damage the tablet.