How should I set the paper thickness adjustment lever on my product?

• This lever adjusts the distance between the print head and the paper to prevent smearing.
  
  Upper position - Plain paper icon - EPSON special media and paper thickness from 0.08 mm to 0.3 mm
  
  Middle Upper position - Envelope icon - Envelopes and paper thickness from 0.4 mm to 1.3 mm
  
  Middle Lower position - Not used
  
  Bottom position - Open icon - This is used to load thick paper through the manual feed slot, in the back of the printer, with a thickness between 0.4 mm and 1.3 mm. After loading a single sheet of heavy paper, the paper thickness lever should be set to the envelope position before printing.