The Omega 166.0115 watch movement from approximately 1860 features a duplex escapement that enables a jumping second function, where the second hand transitions between a slight step and approximately one second intervals. The movement requires a twist motion to start and relies on a bimetallic screw balance, barrel stop-work, and an indirect sub second driven by the escape-wheel pinion. It also includes a direct sweep second and offers key wind and set capabilities alongside a sub second and 12h dual time function.