The NPFW50 Battery Pack from Sony is for use with the NEX series of digital point and shoot cameras. This lithium ion battery pack has a unique feature - a capacity display which lets you know how much juice the battery has before it runs dry. With a capacity of 1080 mAh, this battery can prolong your recording time. It has an output voltage of 7.7 V. You can use this battery as your main camera battery or as a spare component. Carrying a spare battery when going on vacations or expeditions always helps, as you never know when you will get the next chance to charge your electronic devices.