old lighted FIRE ESCAPE sign

Here's another of my 'lighted sign' collection, this one pointed the way to a FIRE ESCAPE, and came from a salvage sale at an old hotel building in Illinois, during a major renovation that took place there several decades ago now. The sign likely isn't nearly as old as the hotel, I'm guessing it dates more from the 1950's. (the hotel was more nineteen-teens or so) It has two standard porcelain light sockets inside (shown w/ a single 15w lamp) that can be accessed by removing one of two small covers on its end with a screwdriver, then sliding either of the (plastic) sign panels to the side. The only label in it is the Underwriter's Laboratory one pictured. Its silver painted steel housing measures about 22" x 7" x 5".