Renata Za13 Zinc-Air Hearing Aid Batteries Come In A Convenient 6-Pack. These 1.45V Batteries Are Mercury-Free (0% Mercury) And Designed Specifically For Hearing Aids And Similar Small Electronic Devices Requiring Reliable, Long-Lasting Power. Key Features: • Zinc-Air Technology For Optimal Performance • 1.45V Power Output • Mercury-Free Composition • 6 Batteries Per Pack • Long Shelf Life When Properly Stored • Specifically Designed For Hearing Aids These Batteries Feature A Protective Tab That Must Be Removed Before Use To Activate The Zinc-Air Cells. Once Activated, The Batteries Will Begin Working And Should Be Used Continuously For Best Results. The Blister Pack Design Helps Protect Unused Batteries And Makes Them Easy To Store And Transport. Proper Storage In A Cool, Dry Place Will Help Maintain Battery Life.