The 85w magsafe1 power adapter has a convenient magnetic connector. so if someone ever trips over it, the cable connection simply disconnects without dropping the macbook pro. this also prevents wear or damage to the cable over time. in addition, the magnetic connector ensures a quick and secure connection to the system. a led indicator on the top of the connector lights up when the connection is made. orange means the device is charging. green means it is fully charged. the power adapter comes with a power cord, for maximum cable length. with its smart design, the power supply is convenient for traveling, as you can easily wind up the cable for easy storage. this power supply charges the lithium polymer battery when the system is on, off, or at rest. it also powers the device when you are not using it on battery power. compatible with 15- or 17-inch macbook pro. original apple with magnetic connector to protect against dropping the macbook fast and secure connection to the system led status indicator smart design color: white