Di (Digitally Integrated Design) is a designation Tamron puts on lenses featuring optical systems designed to meet the performance characteristics of digital SLR cameras. Very compact and lightweight, this lens is the ideal wide-angle zoom lens for any digital SLR camera, as well as any standard photo SLR cameras.
Features like LD glass elements and Internal Focusing put this lens in the same category as the much bigger and more expensive professional Tamron lenses.