Powermax 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. Powermax CR2016 circle batteries are designed not to leak and to hold in power for up to five years in storage under normal conditions. These round lithium batteries come in a pack of 6.