This is a mount adapter for using Yashica Contax lenses on Canon EF mount cameras. Once attached, it fits securely, making removal somewhat difficult, so I had several of them. I believe they are still usable. This is a used item, so there is no warranty. Please consider this only if you understand that it is a used item. Set of 5 metal CY-EOS mount adapters, with red marks for improved lens compatibility. - Model: CY-EOS - Quantity: 5 - Material: Metal - Application: Lens mount adapter - Features: Red mark Thank you for viewing.