Since 2017, Sony watch batteries have been manufactured by Murata
The very same high-quality batteries are available today—only under the Murata brand. 
Murata offers a wide range of micro batteries with high performance and reliability, taking advantage of state-of-the-art design and production technologies.
Features of Murata Micro Batteries
Murata offers a “Smarter” Multidrain System, reducing the number of SKUs required without making compromise.
Murata’s longer-life silver oxide batteries feature the best anti-leakage system in the industry.
All Silver Oxide, Lithium coin, and Alkaline button cells batteries are offered exclusively in tear-strips of 5 cells, marked with a “Use By” (best before) date.
