ACDelco CR2016 lithium coin cell batteries provide reliable energy to many common electronics, such as watches, keyless entry devices, glucose monitors, heart-rate monitors, calculators, and toys. The 3-volt batteries have high energy density to provide a long-lasting power source. They are mercury- and cadmium-free, making them safe for your home and better for the environment. ACDelco CR2016 batteries are designed not to leak and to hold in power for up to five years in storage under normal conditions. Includes 24 CR2016 batteries.