ETA SA G15-21A

The ETA G15-21A is a quartz chronograph movement manufactured by ETA SA. It uses an SR936SW battery with an approximate 48-month life and contains 6 jewels. The movement features a date wheel with position variants to accommodate different dial designs—it may be marked G15.21A-4 or G15.21A-D4, where the trailing digit indicates the date window location. This movement was used in the Invicta 29985 and has been discontinued from the ETA catalog.