Apple Power Adapter/Charger MagSafe2 45W

• Replacement adapter.
• Use an extra adapter for home or work.
• The Apple 45W MagSafe 2 Power Adapter is made specifically for your MacBook Air. Compatible with 13-inch MacBook Air, 11-inch MacBook Air
• It’s held in place magnetically, so if someone should trip over it, the cord disconnects harmlessly and your notebook stays put safely

A replacement adapter might not be the same size, color, shape, or wattage as the original adapter that came with your computer. But it should power and charge your Mac like the adapter that originally came with your computer. 

If you need help using your MagSafe adapter, see Apple Portables: Troubleshooting power adapters.