Unique to Sigma - Widest range with HSM : Super-Wide - 10-20 with maximum aperture of F3.5 throughout entire zoom range : High Image Quality - Two ELD (Extraordinary Low Dispersion) glass elements and a SLD (Special Low Dispersion) glass elements and Four Aspherical lenses : Includes - Petal-type Hood supplied : Specifications : Lens Construction - 13 Elements in 10 Groups : Angle of View - 102.4 - 63.8 degrees : Number of Diaphragm Blades - 7 Blades : Minimum Apertur…