The Battery Kit is the perfect companion to the Charge Station for Wii. The Battery Kit from Nyko allows you to make all your Wii-Remotes compatible with Nykos Charge Station for Wii (sold separately). Each Battery Kit comes with one NiMH rechargeable battery pack good for up to 25 hours of playtime on a single charge. A rubberized battery cover specifically designed to work the Charge Stations dual port charging dock is also included in one of five custom colors. With the Battery Kit from Nyko, all of your Wii-Remotes can easily be upgraded and compatible with Nykos Charge Station for Wii. For those with more then 2 Wii-Remotes, the Battery Kit is the best solution for keeping all of your remotes charged and ready to go!