Lithium-Ion Battery, exclusively for Samsung Smartphones, offers longer battery life, is reliable and safe, having gone through an exhausting testing and certification process. For long travels or extended use, have the peace of mind of an extra Samsung battery on hand when you need it. Developed specifically for the Galaxy Note 4, you can keep it as a spare battery, or use it as a replacement for your existing battery. Charge a spare battery to keep with you in the event your phone is low on battery and you can’t plug in or need to keep using your phone without being tied down to a wall outlet.