The following deal was posted via CNET last week.
http://www.cnet.com/news/buy-one-tablet-headrest-mount-get-a-second-one-free/
The blog post shows the following headrest mounts with a BOGO deal.
http://www.amazon.com/TFY-Universal-Headrest-Without-Protruding/dp/B00IPCJFR4
50 Product Reviews 4.8 out of 5 Stars
http://www.amazon.com/TFY-iPad-Headrest-Mount-Holder/dp/B008TLE1P2
300 Product Reviews - 4.6 out of 5 Stars
The BOGO deal on both mounts are still active.
http://www.cnet.com/news/buy-one-tablet-headrest-mount-get-a-second-one-free/
The blog post shows the following headrest mounts with a BOGO deal.
http://www.amazon.com/TFY-Universal-Headrest-Without-Protruding/dp/B00IPCJFR4
50 Product Reviews 4.8 out of 5 Stars
http://www.amazon.com/TFY-iPad-Headrest-Mount-Holder/dp/B008TLE1P2
300 Product Reviews - 4.6 out of 5 Stars
The BOGO deal on both mounts are still active.