The Sigma 18 to 250mm F3.5 F6.3 HSM OS is a compact and lightweight zoom lens designed for Canon DSLR camera. It offers you a focal length range of 18 mm to 250 mm which enables you to compose superb telephoto as well as wide angle shots. The lens offers a maximum aperture of f/3.5 wide and f/6.3 telephoto. The HMS motor driven AF of the lens provides you with faster and noise-free focusing. The lens is made from thermally stable composite material which gives you a high degree of elasticity and exhibits little variation in its structure in extreme temperatures. The OS system of the camera gives you blur-free image.