Sigma 150-500mm F5-6.3 DG OS HSM is an Auto Focus (AF) Telephoto Zoom lens with 35mm FF max sensor coverage. When mounted on a 35mm FF sensor camera, it will give you an FF equivalent focal range of 150 - 150mm. With the max aperture of only f5 at 150mm, it is considered a slow lens.
This lens features on optical image stabilization which helps capturing sharper images at lower shutter speeds. Sigma 150-500mm F5-6.3 DG OS HSM is not a weather sealed lens, so you have to be extra careful against rain and dust.