Using this Sanyo Sub - C NiCd rechargeable battery is easy. Just insert it into your device that requires a 1.2V power source. When it comes to charging, use a charger suitable for NiCd batteries and follow the charger's instructions. For safety, don't overcharge the battery as it can damage the battery's performance and lifespan. Avoid exposing the battery to extreme temperatures, like very hot or very cold places. To keep it in good shape, charge the battery fully before first use. If you're not going to use the battery for a long time, store it in a cool, dry place. Also, make sure to handle the battery gently to prevent any physical damage. With proper use and care, this battery will serve you well for a long time.