Length of chain 195mm. Probably first half of the 20th century. This is the old wizards chain trick. If you know the secret, you can make the link at the top climb all the way down to the bottom. The chain came with two sets of instructions, one in English and one in German headed Zauberkette (Magic Chain). The trick and instructions came in a paper envelope with the sample number 2732 on it. It clearly came from Germany but the manufacturer is not known.