Lenovo ThinkPad T400s series User Manual page 5

IV. Emergency Calls
The wireless WAN adapter embedded in the computer does not support voice
calls, hence their use for essential communication is not possible, including
emergency calls regarding the E911 rule.
V. Simultaneous use of RF transmitters
The wireless WAN adapter is approved for simultaneous use with certain
wireless transmitters. For a list of those transmitters, refer to the latest
ThinkPad Regulatory Notice, which has been uploaded on the Web site at:
http://www.lenovo.com/think/support
Make sure of the following conditions when you use any other external RF
option device:
1. When you use any other RF option device, you are requested to confirm
that the device conforms to the RF Safety requirement and is approved to
use for your computer.
2. You must follow the RF Safety instructions of the RF option device that
are included in the user manual of the RF option device.
3. If the RF option device is prohibited to use in conjunction with another
transmitters, you must turn off all other wireless features in your
computer.
ThinkPad Regulatory Notice for the Wireless WAN Adapter
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