Check Your AirPort Extreme
Did you know there are eight different models of Apple’s AirPort Extreme Base Station (AEBS)? But only the last three versions offer Gigabit ports and simultaneous dual-band WiFi (2.4 & 5GHz). So if you want to buy a second hand unit on eBay, you better know which one! The way to tell the difference is by their part numbers: MD031LL/A (latest model); MC340LL/A and MB763LL/A or the model numbers: A1408 (latest); A1354 and A1301. All older AirPort Extreme generations should be avoided if you want fast WiFi and fast Ethernet.