diff --git a/doc/manual/faq.rst b/doc/manual/faq.rst
index b98c3f2c1..a53b69689 100644
--- a/doc/manual/faq.rst
+++ b/doc/manual/faq.rst
@@ -89,4 +89,8 @@ feature of pyserial
 `serial_for_url() <http://pyserial.sourceforge.net/pyserial_api.html#serial.serial_for_url>`_
 in order to open a serial device.
 
+The preferred way to specify a serial device is to make use of the ``hwgrep://``
+URL: it allows to select the serial device by its USB vendor ID, product
+ID and/or serial number. Those never change, unlike the device file name.
+
 See the :ref:`TDC001 documentation <tdc001-controller-usage-example>` for an example of ``hwgrep://`` usage.
\ No newline at end of file