3 ms·I'm guessing the hinge was added for the museum display right?by giarc 7y agoI'm guessing the hinge was added for the museum display right?mcguire 7y agoThe pictures are of a replica.giarc 7y agoYou are right. This caption isn't shown unless you click on the image. "Open view of a replica of a bugged US great seal on display at the National Cryptologic Museum in 2005."