This is a set of two portable players. You can connect them to watch on both. The screens are large and easy to see. Since the condition of the cables is not good, please consider this as junk. They were used when going out, so I don't think they were used many times, as the children would each watch one. However, the cable connecting the two players is frayed? and about to break. Therefore, the twin monitor function may or may not work depending on the cable condition. If you have a separate cable, it will work, so this is considered junk. The main units themselves display properly. If you purchase new cables, you should be able to see the video on both. Alternatively, they can be used for parts. You can also watch them from a car's cigarette lighter socket, but the cable is frayed and dangerous, so I'll include it, but it's better not to use it. I recommend purchasing new cables. They can also be charged, so you can use them even where there are no outlets. You can also connect them to a TV (photo 11). Please check photo 12 for the fraying. The remote control has been tested and works. It seems you can also play games, but I haven't used that function, so I don't know much about it. I used colored round stickers to make the cables easier to identify. They can be easily removed, so please peel them off if you are concerned. I am not familiar with technical terms, so I will not be able to answer questions using them. Please understand based on the photos and explanations. I will pack them in the original box. Please understand that these have been stored at home. Please refrain from purchasing if you are overly concerned about condition.