armamentgroup
Shooter
Magpul Back-up Rear Sights Black and FDE $56.95!
http://www.armamentgroup.com/Magpul-MBUS-GEN-2-Polymer-Back-up-Rear-Sight-MAG248.htm
http://www.armamentgroup.com/Magpul-MBUS-GEN-2-Polymer-Back-up-Rear-Sight-MAG248.htm