Olympus 12-100mm F4.0 IS Pro is an Auto Focus (AF) SuperZoom lens with FourThirds max sensor coverage. When mounted on a FourThirds sensor camera, it will give you an FF equivalent focal range of 24 - 200mm. With a max aperture of f4 at 12mm, we can not consider this lens fast on wide end but f4 at 100mm is not too bad for tele end.
This lens features on optical image stabilization which helps capturing sharper images at lower shutter speeds. Olympus 12-100mm F4.0 IS Pro is weather sealed which makes it an ideal lens for outdoor use, especially when coupled with a weather sealed camera body.