Focal Length & Maximum Aperture Magnification: 2.0x
Lens Construction 9 elements in 5 groups
Max. Diameter x Length, Weight 2.8 x 2.1 in, 11.5 oz. / 72.0 x 52.7mm, 325g
Note: This lens is only compatible with fixed focal length L-series lenses 135mm and over, as well as the EF 70-200/2.8L, EF 70-200/2.8L IS, EF 70-200/4L, and EF 100-400/4.5-5.6L. Additionally, please see the lens and/or camera body manual for full compatibility information with the Extender EF 2X III.