AirPcap Tx: USB 802.11b/g Adapter (capture + injection) (298USD)

AirPcap Tx: USB 802.11b/g Adapter (capture + injection) $298.00 
 
AirPcap Tx: Transmit Raw 802.11 Frames on Your Network

In addition to all of the features of AirPcap, AirPcap Tx supports the transmission of raw 802.11 frames on your wireless network. This capability makes AirPcap Tx an invaluable aid in assessing the security of your wireless network. The transmission capability enables several tools to run on your Windows laptop; among them are:

Cain & Abel: a multi-function security tool for Windows, that includes wireless access point and host detection and WEP key recovery.
Aircrack-ng: a well known suite of tools for auditing wireless networks. With it you can run various types of attacks on a wireless network and recover WEP and WPA keys.

AirPcap Tx fully supports these tools, including advanced functionalities that require frame injection, like high-speed WEP key recovery. AirPcap Tx can inject any kind of frame, including control and management frames, at any 802.11b/g rate.
It is important to note that while AirPcap Tx imposes no restrictions on channels used for monitoring 802.11 traffic, AirPcap Tx will only allow transmission on those channels that are permitted by the ship-to country. AirPcap is available in different "flavors" to meet your country's frequency and power requirements.