Canon EF 70-200mm f/2.8L USM Telephoto Zoom Lens Short Description EF Mount L-Series Lens Aperture Range: f/2.8-32 Four UD Optical Elements Inner Focusing System Ultrasonic Autofocus Motor (USM) Focusing Range Limiter Minimum Focus Distance: 4.9' 77mm Filter Thread Diameter Detachable, Rotatable Tripod Collar Compatible w/Extender EF 1.4x II & 2x II