The EF 16-35mm f/2.8L II USM Lens from Canon is a high performance, water-resistant, ultra wide-angle L-series zoom lens. An f/2.8 maximum aperture is effective in low light situations and offers shallow depth of field focus control. The optical design has Key Features EF Mount L-Series Lens Aperture Range: f/2.8-22 UD and Three Aspherical Lens Elements Ultrasonic Autofocus Motor Manual Focus Override Water and Dust Resistant Minimum Focus Distance: 0.9′ Truly Circular Diaphragm 82mm Filter Thread Diameter Lens Hood Included