EF Mount L-Series Lens/Full-Frame Format One Fluorite and One Super UD Element Air Sphere and Fluorine Lens Coatings Ring-Type USM AF Motor, Internal Focus Optical Image Stabilizer with 3 Modes Rotating Zoom Ring & Torque Adjustment Weather-Sealed Design Detachable, Rotatable Tripod Collar Rounded 9-Blade Diaphragm