Canon Extender EF 2x III

 
 
Designed to extend a lenses focal length by a factor of 2x, the redesigned Canon Extender EF 2X III delivers optical performance on par with the finest Canon super telephoto lenses. It features a built-in microcomputer for seamless communication among camera body, lens and extender, features careful lens placement and coatings to minimize ghosting, flare and chromatic aberration, and even has a new Fluorine coating that keeps soiling, smears, fingerprints to a minimum. Extender EF 2X III meets necessary standards in terms of rugged, dustproof and water-resistant construction, and should be in every professional`s camera bag.
 
Specification:
 
Focal Length & Maximum Aperture  Magnification: 2.0x
Lens Construction  9 elements in 5 groups
Max. Diameter x Length, Weight  2.8 x 2.1 in, 11.5 oz. / 72.0 x 52.7mm, 325g