A Preußen veteran of the 1870 War: the subject's medals are the Kriegsdenkmünze für 1870 - 71 (with four bars), Erinnerungs-Medaille (issued in 1897), and the Allgemeines Ehrenzeichen. The ribbon device worn below the Spange is one of the three classes of Dienstauszeichnung für Unteroffiziere und Soldaten.
This gentleman most likely begain his military career in the 1860s and served in some Reserve or Landwehr capacity through at least 1897.
Brian, can you provide a close-up scan of the bars? Is the photograph dated?
Chas.