The PROMASTER 2x Autofocus Teleconverter is compact and lightweight and adds photographic versatility without the expense of an extra lens. This converter allows the focal length of your lens to be extended by a factor of 2 times. The 1.7x factor has a minimal reduction to your effective aperture of only 2 stops. The PROMASTER 2x Autofocus Teleconverter communicates with most lenses for full compatibility.
For use with lenses with a maximum aperature of f/3.5 or higher