Canons second-generation Wireless File Transmitter WFT-E2A incorporates a number of significant new features into a robust, camera-powered system to make wireless transfer faster, simpler and less cumbersome than ever. WFT-E2A is smaller, attaches to the side of the EOS-1D Mark III, transfers images wirelessly through either 802.11 B or G, has USB and Ethernet connections for situations where wireless access is limited, as well as a more powerful antenna, capable of transmission up to 150 feet from the computer, or an accessory router/access point receiver. It can connect to a third-party GPS device via USB; generating GPS information in the images EXIF data. Or, you can plug a compatible USB v.2.0 hard drive into the transmitters USB port, and actually shoot directly to a large portable hard drive. Dust- and water-resistance are also matched with the EOS-1D Mark III body. (Note: the previous WFT-E1A Wireless Transmitter unit is not compatible with the EOS-1D Mark III camera.) -Can be new, or used, we will buy any, but must be functional.