This article is from the Toyota Tundra FAQ, by Steve Yee with numerous contributions by others.
These rear view mirrors that you see that "blink" as the turn signal is
activated are made by a company called Muth Mirror Systems. First made popular
by the Ford Expedition, there are two add ons available from Muth that can be
adapted to the Tundra.
1) A Wide Angle Signal mirror, which is an add on to your existing mirrors
2) The original Automotive Signal mirror, which replaces the driver's side and
passenger mirrors on your Tundra.
To locate Muth Mirror Systems, go to http://www.kwmuth.com.
 
Continue to: