Never miss a moment with the world’s longest lasting hearing aid battery – now with child-resistant packaging! This box of 48 batteries (size 312) includes Rayovac’s new „Active Core Technology,“ providing unparalleled power on demand, longer lasting performance and increased durability. No battery lasts longer! Today’s hearing aids require the best. Rayovac Proline delivers the best in any situation, from mountain climbing to spending time with your family. Take advantage of advanced, high-drain hearing aid features like automatic environment sensing or ear-to-ear directionality without having to constantly replace your batteries. FeaturesIncludes (48) size 312 batteriesWorld’s longest lasting battery (based on ANSI / IEC testing)Child-resistant packagingAir optimization system uses air more efficiently to deliver consistent performance in all usage conditions.Zinc Air batteries are mercury-free and therefore more environmentally-friendly