Ridgid Genuine OEM R840087 18V Hyper Lithium-Ion 4AH Single Battery HYPER LITHIUM ION TECHNOLOGY allows for improved performance from previous generations of batteries COLD WEATHER PERFORMANCE: These batteries can work in temperatures as low as -4 degrees Fahrenheit (-20 degrees Celsius) PROTECTIVE ENGINEERING: The layout of the fuel cells inside the battery are designed to help protect the battery from overheating, overloading, and overcharging ONBOARD FUEL GAUGE lets you know how much power is left on the battery. Now you can know when youll need to recharge TECHNICAL SPECIFICATIONS: 4AH, 18V Lithium Ion, Recharge Range of 32F - 120F (0C - 50C), 72Wh