Renata Size 312 Hearing Aid Battery - 1.45V Zinc Air Battery - Renata hearing aid batteries are ISO 9001:2008 and ISO/TS 16949 certified. Renata zinc air batteries provide you with superior battery life, whether you are using them for analog, digital, or ultra high hearing devices. It provides a long service life with a guaranteed high cell voltage thanks to a patented cathode technology makes frequent battery changing redundant and promises the best sound. Each individual cell is tested for its electrical and mechanical characteristics in accordance with its specifications. Additional Details ------------------------------ Product description: Renata Size 312 Hearing Aid Battery - 1.45V Zinc Air Battery - Renata hearing aid batteries are ISO 9001:2008 and ISO/TS 16949 certified. Renata zinc air batteries provide you with superior battery life, whether you are using them for analog, digital, or ultra high hearing devices. It provides a long service life with a guaranteed high cell voltage thanks to a patented cathode technology makes frequent battery changing redundant and promises the best sound. Each individual cell is tested for its electrical and mechanical characteristics in accordance with its specifications.