Spring driven with lever escapement. Manual winding. Caliber Rax 6051-21.
In a bracelet made of yellow Bakelite a watch is embedded. Opposite the watch there is a spring that allows the bracelet to expand when putting it on and on the side slit that opens when placing and removing the bracelet.
In the bracelet made probably around 1940 is embedded watch from the 1970s. Movement was made by the Swiss company Ronda. It is not known where the bracelet was produced; the assumption that it was in the United States is based on the fact that there is a greater number of very similar pieces preserved there. It is also known that such Bakelite bracelets were made in order to incorporate watches. On e-bay one can see a couple of almost identical bracelets dating from around 1940, with a variety of embedded watches.