The Sigma 10-20mm f/4-5.6 EX DC HSM EF-mount lens is a superwide-angle 2x zoom lens. This lens is designed for use with APS-C digital SLR cameras and offers the user a noiseless high-speed focusing system. With excellent image quality at all focal lengths, good control of the chromatic aberration, and a well-controlled distrotion, this lens has everything that a zoom lens can offer - and more. Add this great zoom lens to your collection today and you will surely not be disappointed with its exceptional quality and performance.