Lens extension and retraction. Aperture blade opening and closing operation. The above have been confirmed. There is dust on the lens, but I don't think there is any mold. ※ Please note that this is a used item, and I do not have the specialized knowledge of a camera store, so there may be oversights. Please assume that anything not mentioned has not been checked. We cannot provide support or warranty for any changes in condition or malfunctions after receipt. Please only purchase if you can accept this. Returns are not accepted as this is a used item.