High-performance, Wide-aperture 400mm f/2.8 Super-telephoto Lens, Exclusively for EOS R-series cameras.. Optically Identical to EF 400mm f/2.8L IS III USM lens; Minimum Focusing Distance of 8.20 ft. / 2.5 m.. Optical Image Stabilization with up to 5.5 Stops* of Shake Correction, Including Three IS Operation Modes.. Super Spectra Coating (SSC) and Air Sphere Coating (ASC) Helps Minimize Ghosting and Flare.. Compatible with Canon RF 1.4x and 2x Extenders.