Thank you for viewing. This item was given to me, and I am selling it because I don't use it. I haven't tested the functionality as I don't have a telephoto lens. The following is an AI-generated description: The Canon EXTENDER EF 1.4x is a high-performance teleconverter that extends the focal length by 1.4x. - Brand: Canon - Model Name: EXTENDER EF 1.4x - Country of Manufacture: Japan - Magnification: 1.4x - Included Accessories: Lens cap Thank you for viewing.