Lens extension and retraction. Opening and closing of the internal blades. The above have been confirmed. There is dust on the lens, but I believe there is no mold. ※ Please note that this is a used item, and I do not possess 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 purchase only if you can accept this. Returns are not accepted as this is a used item.