In 2018 Citizen announced it developed the Caliber 0100 Eco-Drive prototype autonomous high-accuracy quartz watch movement which is claimed to be accurate to ± 1 second per year. Key elements to obtain the high claimed accuracy are applying a for a watch unusual shaped (AT-cut) quartz crystal operated at 223 or frequency, thermal compensation and hand selecting pre-aged crystals. Besides that AT-cut variations allow for greater temperature tolerances, specifically in the range of , they exhibit reduced deviations caused by gravitational orientation changes. As a result, errors caused by spatial orientation and positioning become less of a concern. The Caliber 0100 movement in 2018 was not available for sale to the public, the technology inside the movement will be introduced in future models. In March 2019 three limited edition wrist watch models with the Caliber 0100 movement were announced to become available for sale with deliveries expected around the 2019 fall.