I previously purchased and used this at DCM. You can fit two regular pet sheet pads on one side (or one wide pad). There is a whitish stain-like mark on the tray, but it is not dirt; it is due to the deterioration of the plastic surface and will not come off even after cleaning. There is no problem with use. It has been used for several years, so there are some rust on parts of the fence and small chips on the frame. It can be assembled without tools, just by inserting the screws. The following is the description from the official website: ● Also for toilet training your dog ● No tools required ● Customer assembly ● Just insert the pins! Easy assembly! ● Easy opening and closing with a sliding door ● Waterproof wrapping. ● Size: Approximately W97.5 x D66.5 x H55.5cm Pet cage, house, circle Small dogs, medium-sized dogs