Each Wii U owners know the likely the battery is supplied by Nintendo for the gamepad is so weak that no later than every 3 hours it runs out of steam and you have to connect the charging cable. This was so far the only thing that bothered me at the Wii U, otherwise I love the console. This accessory can be the finally remedy. The installation was very easy and the member actually holds by 6-7 hours.
Since Nintendo can even learn a lot, so a battery would have heard from the beginning in the gamepad.
For this product there is of me a strong buy recommendation.