60 PowerOne Mercury Free Batteries, Size 312 Zinc Air Hearing Aid Batteries. (60 batteries Comfort dial pack, 10 cards of 6 cells each). VARTA Microbattery with its brand Power One has over 100 years of experience in developing innovative battery technologies. Featuring with its consumer-focused extra long tabs, Power One batteries are manufactured at the world&apos's most up-to-date and biggest production site for hearing aid batteries in Ellwangen/Germany-well recognized for manufacturing quality and detailed precision. Subject to Germany&apos's stringent safety guidelines and quality checks, every cell is tested for its electrical and mechanical characteristics in compliance with its specification.