Mid-series (1999) full frame Sigma zoom lens for Nikon autofocus bodies.  Very clean, I see no major marks or damage of any sort, glass is clean inside, aperture is clean and snappy.  This is a decent quality full frame lens with 2 aspherical elements and the ability to focus to 19.5in if I'm to believe the Internet.

Best specs I could find:
__________________________________


Focal length range: 28mm - 200mm [7.1X zoom ratio]
Speed range: F/3.5 @ 28mm - F/5.6 @ 200mm
Maximum format: 35mm full frame
Mount and Flange focal distance: Canon EF [44mm]

Nikon F [46.5mm]

Diagonal angle of view: 75.4° @ 28mm - 12.3° @ 200mm
Lens construction: 17 elements in 14 groups
1 ASPH, 1 SLD
Internal focusing (IF)