Maxell is the worlds leading manufacturer of Mercury free environmentally friendly watch cells. Silver Oxide cells are the primary long life cells used in quartz wrist watches, where high-energy density per unit volume abd a stable operating voltage are required. To mark the distinction between the Mercury Free Silver Oxide batteries and standard Silver Oxide batteries, Maxell have stamped the Mercury Free variant with a Hg 0% design registered logo. Please dispose of used batteries in a responsible manner. Keep out of reach of small children.