Guessing 1930's but they were around for years. The wiring looks completely intact and serviceable. Wiring diagram could likely be used to hook it into a modern house line. While dusting it out I noticed the bells were brass. It took a while to get the black paint off them but they have shined up nicely. The case is intact with some light scratches. Hinges and locking screw work smoothly. If someone wanted the unit just for steampunk fodder this would make it worth the price. Especially as it could likely be wired to ring outside of phone use. $50 OBO - Will trade for militaria.