This example of the celebrated Helios 44M, with M42 screw fitting is in excellent condition. 

The M42 screw fits Pentax, Zenith and Practica as well as others. It can easily be adapted to fit more modern digital cameras (if that’s your thing!) 

The glass is clear (see images) and the lens stops down perfectly smoothly and accurately. 

Known for its characteristic ‘Bokeh’ this lens has been celebrated for many years, particularly as a portrait lens.

Comes boxed (in Sigma box) and with front lens cap.