text: **COARSE KNOB ADJUSTMENT - Model AY11240**
  **MICROSCOPE USAGE**
  
  1. The coarse adjustment knob has an adjustable heavy-light nut 
   (See Fig.1). 
  2. To adjust the knob loosen or tighten the nut. 
   NOTE: Adjusting the nut too tight will make focusing difficult. 
   Adjusting the nut too loose will cause the tube to slide. 
  
  BARSKA Model AY11228 and Model AY11232 are designed for 
  biological studies such as specimen examination. They can also 
  be used for examining bacteria and for general clinical and medical 
  studies. Simple design and use is especially useful for school 
  classroom instruction. 