This 20-Pack of TangsFire AA Rechargeable Ni-MH Batteries are made of high quality material, offering peak performance. They are super convenient with their rechargeable feature. You can recharge them anywhere, no need to buy pack after pack of wasted batteries. These batteries are high strength, extremely durable and safe to use anywhere. With high capacity, they can supply power for an extended period of time and are great in either high temperature operations as well as low temperature.