Designed for use in professional devices, Energizer Industrial 9V Batteries are top of the line in terms of production and reliability. These alkaline cells feature a potent Zinc Manganese Dioxide (Zn/MnO2) chemistry that gives them the power needed for high drain devices like hand-held radios and the longevity needed for smoke alarms and digital clocks. Their ability to operate in severe hot and cold temperatures makes them perfect for use in any work environment. The EN22s come with a shelf life of 5 years, allowing you to keep them around the office for when you need them most.