Canon EF 400mm f/4L DO IS USM (Multi-layer Diffractive Optical Elements) Image Stabilizer USM AutoFocus Lens with Case Hood & 52mm Gel Holder - USA -
Canon's breakthrough multi-layer diffractive optical lens technology provides photographers with superior super-telephoto performance in a smaller and lighter design with enhanced correction for chromatic aberrations. Canon also added their highly effective Image Stabilization system that gives the equivalent effect of a shutter speed two stops faster. And, it's built it to Canon's professional standards with fast AF, full-time mechanical focus and dust and water-resistant construction.
The Canon 400mm F/4L is popular because customers like the following qualities of the Canon 400mm F/4L: Fast / accurate auto-focus, Lightweight and Strong construction.