Features a magnetic DC connector allowing the cord to disconnect harmlessly from the MacBook Pro, also preventing fraying and weakening of the cable • Magnetic DC helps guide the plug into place • Cord folds neatly around the adapter for storage • Power adapter recharges the lithium polymer battery while the system is off, on, or in sleep mode • 85W • Compatible with MacBook Pro with Retina display • Comes with AC cord and AC wall adapter The 85W MagSafe 2 Power Adapter features a magnetic DC connector so if someone trips over it, the lead disconnects harmlessly and your MacBook Pro stays put safely. It also helps prevent fraying or weakening of the cables over time. In addition, the magnetic DC helps guide the plug into the system for a quick and secure connection.