The Canon EF-S 55-250mm f4-5.6 IS II Lens is a lightweight, affordable first or second lens to complement your entry-level or midrange digital SLR. Incorporating Canon's Optical Image Stabilizer technology, this telephoto zoom lens captures long distance, low-light shots far better than many comparable lenses, helping you photograph the far-off action of athletes or zoom in for an intimate portrait with a blurred background. With its 400mm-equivalent focal length, you get the reach and angle of view desirable for shooting portraits and sports, or just to bring the scenes in closer, with the image stabilization essential to keep those long telephoto shots from blurring from camera shake. More significantly, the image stabilizer effect creates an equivalent shutter speed of roughly four stops faster than the same size lens without an image stabilizer.
I'm not a photographer and I might be wrong, but this seems to be the same item on Amazon for $300.