This is a Lithium Ion battery that has a capacity of 2000mAh and operates at 3.7V. This 3.7V cylindrical battery includes built-in protection against over voltage, over current, and minimum voltage. The 3.7V 2000mAh lithium ion rechargeable battery has a wide range of applications in robotics science projects, electric toys, quadcopters and drones. Please use caution when using this 3.7 cylindrical battery in wearable projects. Package Includes: 1 x 3.7V 2000mAh Lithium Ion Cylindrical Battery.