Tokina AT-X 12-24mm AF Pro DX

Manufacturer's Description:

"The all-new AT-X 124 AF PRO DX lens is Tokina's first lens designed for use exclusively on Canon and Nikon Digital SLR cameras having an APS-C sized sensor.

This lens gives the Digital Photographer an ultra wide-angle zoom lens that has the equivalent of an 18-36mm zoom range on a 35mm
film camera while maintaining a bright constant aperture of f/4."