This is a used Canon EF 20-35mm f/3.5-4.5 USM lens. It functions without any problems and the exterior is not dirty. It's a fairly old lens, but being a 20mm, it's relatively wide, making it sufficient for landscapes and taking photos of the night sky. However, as it's an old lens, Canon's support ended a long time ago, so please understand that it cannot be repaired if it breaks. Please purchase with this in mind. There is no noticeable dust inside the lens, but there is some dust present, so we ask that those who are sensitive to this refrain from purchasing. We are selling it at a bargain price, so please understand that it is non-refundable and non-returnable. No price reductions.