Swiss-powered Renata Zinc Air Batteries. Renata, a company of the Swatch Group, is an industry leader in the design and manufacture of button cell batteries. Thanks to an optimally high and constant voltage, as well as Renata's latest improvement to its chemistry, Renata maratone+ zinc air batteries provide you with superior battery life, whether you are using them for analog, digital, or ultra high hearing devices. Enjoy FREE shipping worldwide when you choose Postal Service as your shipping option at Checkout and receive a FREE "Battery Buddy", battery holder keychain when you order a carton or more of batteries.