text: BARSKA Model AY11228 is a fixed power stereo microscope. It is 
  constructed with two optical paths at the same angle. It is 
  equipped with transmitted illumination and oblique illumination. 
  By using this instrument, the user can observe and enlarge the 
  right side stereo image. BARSKA Model AY11232 is a zoom stereo 
  microscope. The object being viewed is enlarged through two 
  identical sized sets of right and left eye lenses. The zoom provides 
  different magnification and features an inversion system which 
  allows the image to be viewed normally and right side up. 
  
  Heavy-Light 
  Adjustment Nut 
  
  **Fig. 1- Coarse Adjustment Knob**
  
  **6**