What are the key features and specifications of the Sigma UC Zoom 70-210mm lens?

The Sigma UC Zoom 70-210mm lens is a telephoto zoom lens with a focal length range of 70-210mm. It has a maximum aperture of f/4-5.6 and uses a bayonet mount. The lens is designed for use with digital SLR cameras and offers a versatile zoom range for capturing distant subjects.