Featuring a unique optical design and paired with advanced image stabilization technologies, the Canon EF 400mm f/4 DO IS II USM is a super telephoto lens characterized by its relative lightweight and compact form factor. Gapless dual-layer diffractive optics are employed within this lens' construction to produce a smaller, lighter 400mm option with enhanced correction for chromatic and spherical aberrations. Aspherical and UD elements are also used to further reduce distortions and a Sub Wavelength Coating contribute to increased clarity and contrast. Complementing the sophisticated optical layout, a four stop-effective Image Stabilizer helps to minimize the appearance of camera shake and can be dedicated to different styles of shooting. Ideally positioned as a versatile option for sports and wildlife photographers, this lens' high-performance attributes and natural handling render this a viable telephoto option for a variety of applications.