ETA SA 2331

The ISA caliber 2331 is a quartz movement manufactured in China. It uses an SR920SW battery providing an estimated power reserve of 66 months and features a battery-saving function that engages when the crown is pulled to the time-setting position. The movement incorporates 371 jewels and includes a capacitor-based reset procedure—if the movement does not work correctly after battery insertion, a reboot can be performed by briefly connecting the indicated capacitor with metallic tweezers to ensure proper initialization. This caliber has been discontinued.