From the ManufacturerThe Canon EF 24-70mm standard zoom lens does what many pros thought couldn't be done--it replaces the L-series 28-70mm f/2.8 lens with something even better. The lens offers extended coverage to an ultra-wide-angle 24mm, making it ideal for digital as well as film shooters. The new processing unit, meanwhile, makes the autofocus (AF) faster than ever. And thanks to the two aspherical elements and a totally new UD glass element, the optics are far superior to the earlier lens. Sealed and gasketed against dust and moisture, the EF 24-70mm lens carries a one-year warranty.Focal length: 24-70mm Maximum aperture: 1:2.8 Lens construction: 16 elements in 13 groups Diagonal angle of view: 74 to 29 degrees Focus adjustment: Front-focusing method Closest focusing distance: 1.25 feet Zoom system: Rotating type Filter size: 77mm Dimensions: 3.3 inches in diameter, 4.9 inches long Weight: 2.1 pounds The Canon EF 24-70mm standard zoom lens does what many pros thought couldn't be done--it replaces the L-series 28-70mm f/2.8 lens with something even better. The lens offers extended coverage to an ultra-wide-angle 24mm, making it ideal for digital as well as film shooters. The new processing unit, meanwhile, makes the autofocus (AF) faster than ever. And thanks to the two aspherical elements and a totally new UD glass element, the optics are far superior to the earlier lens. Sealed and gasketed against dust and moisture, the EF 24-70mm lens carries a one-year warranty.Product DescriptionFilter size: 77 mm, Closest Focusing Distance: 1.25 feet.