Good, used telephoto gear from SIGMA. On full-frame Canon the reach would be 140 to 400 mm, using the extender. On a good APS-C sensor, you'd bring to play the crop multiplier, pushing the reach out to approximately 200 to 600 mm! Both are used (see photos for some burnishing and wear marks) but both are sound. The glass is clean and the zoom is snug. The $470 price includes packing and shipping to any place in the lower 48 states. Get this in time for autumn's elk, deer, moose, migrating birds, and the great raptors.
