The Eterna 1459U watch movement is a result of joint development by Hamilton-Buren, Breitling, and Heuer in the period of 1969 onwards. It incorporates the Dubois-Depraz 8510 module on a modified Buren 1281 base. Notable features include a crown positioned at 9 o'clock, a micro rotor, and a double excenter regulator for curb pins and stud carrier. The indirectly driven minute hand allows for a low profile design. This movement is an automatic chronograph with functions such as a 60-second, 30-minute, and 12-hour chronograph, a date display set by changing 21-24 hours, and automatic winding capabilities.