Sigma 20mm f/1.4 DG HSM Art Lens for Sigma SA 412956

SA Mount Lens/Full-Frame Format Aperture Range: f/1.4 to f/16 Two FLD Elements and Five SLD Elements Two Aspherical Elements Super Multi-Layer Coating Hyper Sonic AF Motor, Manual Override Rounded 9-Blade Diaphragm TSC Material, Brass Bayonet Mount Built-In Petal-Shaped Lens Hood Compatible with Sigma USB Dock