379/Sr521sw Energizer Watch Batteries This is a new set of 10 Energizer #379 (Sr521sw) watch batteries There are 5 batteries in a package Energizer - trusted power for proven performance and reliability Brand new & guaranteed factory fresh. The shelf life on Energizer batteries is 5 to 10 years These batteries are commonly required for Swatch, Fossil, Timex and Casio Energizer's reported failure rate is far less than 1/1000 of 1% This devotion to consistent quality has led it to control over 70% of market share in Switzerland, one of the world's leading watch producing countries Energizer is respected world wide for its uncompromising quality and consistent performance Energizer's technological leadership produces a variety of miniature batteries which are trusted for use by the best names in watch, computer, keyless entry, consumer electronics and hearing aid industries