AirPort Extreme 802.11n Enabler... If you have a Mac with an Intel Core 2 Duo processor (except the 17-inch, 1.83GHz iMac) or a Mac Pro with AirPort Extreme, you can enable it to access an 802.11n wireless network using the AirPort Extreme 802.11n Enabler software.
Many Mac computers with an Intel Core 2 Duo and all Mac Pro computers with AirPort Extreme can be enabled to access 802.11n-based wireless networks. If you purchased one of these Macs, you can use the AirPort Extreme 802.11n Enabler software to activate this advanced wireless capability.
Important note: The Enabler is included free with the new AirPort Extreme Base Station with 802.11n. If you purchase a new AirPort Extreme Base Station, you do not need to purchase the Enabler separately.
These Macs have the 802.11n hardware built-in:
Do you need the AirPort Extreme 802.11n Enabler? Before purchasing the 802.11n Enabler software, please check to make sure that your Mac does not already have the 802.11n enabler already installed.