The BAT-CR1620/GP is a GP Batteries lithium coin cell battery. It is a 3.0V cell with a diameter of 16mm and a height of 2.0mm. It has a capacity of 160 mAh and a cycle/shelf life of about 2-4 years. It is non-rechargeable and is commonly used in small devices such as calculators, keyless entry systems, watches, and other small electronics.