Canon offers the factory-refurbished Canon EF 17-40mm f/4L USM Ultra Wide Angle Zoom Camera Lens, model no. 8806A002, for $571.19 with free shipping. That's $148 under the lowest total in-stock price we could find for a new unit, although we saw a refurb for $33 less in June. This 1.1-lb. lens is for use with most Canon SLR cameras. A 90-day Canon warranty applies.