This 1906 Dueber Hampden, which started out its life as a pocket watch but was re-cased as a wristwatch probably in the early 1920s. Mail-order conversion kits for transforming pocket watches to wristwatches, such as the kit used to transform this piece, were popular in the 1920s. The movement is "The Four Hundred", which is a "lever-set" movement -- i.e., the time is set by first pulling out a small lever then rotating the crown, rather than pulling out the crown and rotating it as with modern movements. The lever can be seen at the 5:00 position.