Renata CR1620 Lithium 10pcs/pkg

Lithium button batteries can be used e.g. in pocket calculators, heart rate monitors and keychain remotes. The numbers in the CR identifier indicate the cell’s physical dimensions, e.g. CR2032 = 20 mm x 3.2 mm.
Battery names vary slightly depending on the manufacturer, and the documents tab allows you access to a comparison table for various batteries.