Pentax DFA645 Macro 90mm F2.8 is an Auto Focus (AF) Macro Prime lens with 645 max sensor coverage. When mounted on a 645 sensor camera, it will give you an FF equivalent focal range of 70.2mm. With a max aperture of f2.8, this is a fast lens.
This lens features on optical image stabilization which helps capturing sharper images at lower shutter speeds. Pentax DFA645 Macro 90mm F2.8 is not a weather sealed lens, so you have to be extra careful against rain and dust.