The Eterna 1486K is a mechanical watch movement with manual winding and sub-second functions. It features a bimetallic screw balance and a stem mechanism without a setting-lever spring. The bridge shapes may vary from the Ebel 8.75''' model. Variations exist between the Eterna 1486K and other movements such as the 158, 159, 185, 208, 212, 238, 246, 251, 259, 261, and 277, although specific differences are not known. It was commonly used around 1925.