Sigma 1.4X EX AF APO Teleconverter (Nikon) with Caps and Lens Case Sigma 1.4x EX DG APO Tele-Converter - Front &amp; Rear Lens Caps - Soft Case - Sigma 1 Year North and South America Limited Warranty (3 Year USA Extended Warranty for a Total of 4 Years from Date of Purchase) Construction: 3 Groups /5 Elements Angle of view: F stop range: Closest Focusing Distance: