The Unitas 289 watch movement offers a range of options for customization and precision adjustment. It features different bridge shapes and can be equipped with either an Incastar regulator or a Triostat regulator. The Incastar regulator stands out as the only large-scale produced regulator with a free oscillating hairspring, eliminating any isochronism error caused by the gap between the regulator pins. On the other hand, the Triostat regulator includes three adjustment features for precise speed and regulator pin-width, as well as a mobile stud carrier. The exact differences between the variations, such as 72, 72-6, 72-7, 721, 723, 725, and 725-7, have not been specified. Additionally, this movement is capable of manual winding, includes a sweep second hand, and has the option of a 24-hour display.