Say goodbye to expensive batteries with the Mad Catz Rechargeable Battery Pak for the Wii Fit Balance Board. 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.
this battery pack does what it is supposed to do. But . . . the first time I charged it from the Wii USB port, the charge light came on for one second and went off. The next day, I put it in the Wii Fit balance board and it worked so it must have charged just fine. However, it only ran for about four hours over the next three days before it died. So I charged it again and I'll see how long it lasts this time. If it has to be charged every third day, it will be a pain in the neck. But if it holds the charge for the advertised 20 hours it'll be a bargain.