Olympus 150-400mm F4.5 TC 1.25x IS is an Auto Focus (AF) Telephoto Zoom lens with FourThirds max sensor coverage. When mounted on a FourThirds sensor camera, it will give you an FF equivalent focal range of 300mm. With the max apertures of only f4.5 at 150mm, and f4.5 at 400mm, the lens is quite slow at both ends.
This lens features on optical image stabilization which helps capturing sharper images at lower shutter speeds. Olympus 150-400mm F4.5 TC 1.25x IS is weather sealed which makes it an ideal lens for outdoor use, especially when coupled with a weather sealed camera body.