Sigma 800mm f/5.6 APO is an ultra telephoto zoom lens ideal for sports and wildlife photography. Two SLD (Super Low Dispersion) glass elements provide excellent color correction and sharpness throughout the entire zoom range. Multi-layer lens coating technology and lens design formula reduces flare and ghosting. Rear insertion 46mm filters with provision for easy rotation of polarizing filters. Compatible with the Sigma’s APO dedicated Tele converter 1.4x and 2x to provide additional focal length as a 1120mm F8 MF or 1600mm F11MF lens respectively.