Rayovac Extra Advanced Size 13 (60 batteries)

Zinc-air battery that uses outside air as an energy source. An adhesive safety tape ensures its freshness (up to 4 years), until you are ready to use it. To activate the battery, simply remove the adhesive tape. After removing the tape, wait about a minute before inserting the battery into your handset. This allows sufficient time for air to enter and activate the battery components. Reattaching the security tape after removing it will not extend the life of the battery.