This is a controller for the NEC PC Engine Duo, a video game console released in Japan in 1991. Detailed operational checks in actual use have not been performed. There is no equipment to verify operation. Due to a lack of specialized knowledge, the condition cannot be determined. This is a used item that has not been maintained, so there is a possibility of defects. This is considered a junk item. Would anyone who can take parts or repair it be interested? As this is a used item, dirt and scratches are noticeable. Please note that we cannot completely clean it.