Sigma 50mm f/1.4 DG HSM Art Lens for Nikon F

Key Features
Aperture Range: f/1.4 to f/16
One Molded Glass Aspherical Element
Three Special Low Dispersion Elements
Super Multi-Layer Coating
Floating System & Large Diameter Design
Hyper Sonic AF Motor
Rounded Nine-Blade Diaphragm
Thermally Stable Composite Material
Brass Bayonet Mount
Compatible with Sigma USB Dock