The ETA 1230 is a manual wind mechanical watch movement that features sub second, date, and sweep seconds functions. It is often or always signed as Femga 500. There are notable similarities between the Femga 500, 502, 520, and Precimax 250, 250SC, 400, 450 watch movement families, but the precise relationship between the French Femga and Swiss Precimax movements remains unknown.