I'm not sure if this is the right power supply for your Mac Book. Before buying, check your Mac Book model so you can order the correct charger for your MacBook. Compatible MacBook Pro Models Compatible with 15" or 17" Mac Book Pro Models: MacBook Pro (Retina, 15-inch, Mid 2015) MJLU2, MJLT2 MacBook Pro (Retina, 15-inch, Mid 2014) MGXC2, MGXA2 MacBook Pro (Retina, 15-inch, Late 2013) ME293, ME294 MacBook Pro (Retina, 15-inch, Early 2013) ME664, ME665 MacBook Pro (Retina, 15-inch, Mid 2012) MC975, MC976 MacBook Pro (Retina, 17-inch, Mid 2015) MJLU2, MJLT2 MacBook Pro (Retina, 17-inch, Mid 2014) MGXC2, MGXA2 MacBook Pro (Retina, 17-inch, Late 2013) ME293, ME294 MacBook Pro (Retina, 17-inch, Early 2013) ME664, ME665 MacBook Pro (Retina, 17-inch, Mid 2012) MC975, MC976 Compatible with 13-inch Mac Book Pro: MacBook Pro (Retina, 13-inch, Early 2015) MF839, MF840, MF841, MF843 MacBook Pro (Retina, 13-inch, Mid 2014) MGX72, MGX82, MGX92 MacBook Pro (Retina, 13-inch, Late 2013) ME864, ME865, ME866 MacBook Pro (Retina, 13-inch, Early 2013) MD212, ME662 MacBook Pro (Retina, 13-inch, Late 2012) MD212, MD213 Note: -1. Keep it dry while charging. Do not place the charger on flammable materials in order to avoid accidents during charging. -2.Do not use this charger with the wrong model of Mac Book. -3.Do not use it on extreme days such as thunderstorms.