Although the Circle Pad Pro requires just one AAA battery, reports from Japan have suggested that a single battery affords up to 480 hours of play time.
The specific figure is provided in the Circle Pad Pro's manual, ONM reports.
The compartment housing the battery is said to be easily accessible, so you don't have to worry about fiddling with screwdrivers.
The controversial peripheral is scheduled to be released in Japan on December 10 alongside Monster Hunter 3G. The attachment is slated for a European release on January 27.
The Circle Pad Pro will available in Europe as a standalone accessory or as part of a limited edition Resident Evil: Revelations bundle.