Wii Fit Battery and Charger

Simply remove the battery cover and batteries from your Balance Board and replace them with the Battery Pak for up to 20 hours of continuous energy. The included USB charge cable compatible with the Wii and PCs makes recharging the internal batteries easy and convenient.

I agree with the points stated above and would normally give this product 3 stars, but you can't argue with the price of the used ones. Due the the limited play time I'd recommend getting two of these babies and charge one whilst using the other.