The Giga-tek CR1220 3V Lithium battery pack of 5 is a reliable and long-lasting power source for various devices. Each battery in the pack has a nominal voltage of 3V and a capacity of 40mAh. These batteries are perfect for small electronic devices such as calculators, watches, and remote controls. The lithium technology used in the batteries provides a higher energy density and longer shelf life than traditional alkaline batteries. The pack of 5 ensures that you always have a backup battery when you need it.