Ⅰ: Product series: three-digit   

     166: series 166 switch

Ⅱ: Figure dimension(length×width): double-digit

      83: 8.35mm×7.15mm

Ⅲ: Free Position: double-digit

      50: 5.0mm

Ⅴ: Operation Force: double-digit

      22: 220gf     

Ⅵ: Fixed Method:single-digit

     0: SMT, type "一" terminal

     1: SMT, type "Z" terminal

     2: SMT, type "V"terminal

   3: DIP, type "S"terminal

   4: DIP, type "八"terminal

     5: DIP, direction of switch function

         and mounting pin is vertical

     6: SMT, with a grounding terminal on the housing

Ⅶ: Life Time: single-digit

   1: 10000 times

   2: 20000 times

   3: 35000 times

Ⅷ: Derivative code: single-digit

Ⅸ: Package: single-digit

   0=plastic bag       1=shrinked plastic bag

   2=tape package     3=tube package

   4=foam package    5=undetermined

    6=plastic bag without Halogen

    7=shrinked plastic bag without Halogen

    8=tape package without Halogen

    9=tube and foam package without Halogen