The Canon EF Promaster Spectrum 7 1.7x Teleconverter is specifically designed for SLR DSLR cameras with Canon EF lenses. This teleconverter features a maximum aperture of f/1.7 and is compatible with Canon brand cameras. With its auto focus type and Canon EF mount, this teleconverter is a great accessory for those looking to extend the focal length of their Canon lenses for added versatility in their photography.