Ⅰ: Code of product series: three-digit

      158: series 158 tact switch

Ⅱ: Dimension of product: single-digit

      0: length×width=6.2×6.2mm

      1: length×width=6.8×6.8mm

Ⅲ: Height of product (Free position): double-digit

       25: 2.5mm       31: 3.1mm

       35: 3.5mm       36: 3.65mm

       37: 3.7mm       43: 4.3mm

       45: 4.55mm     50: 5.0mm

       57: 5.65mm     60: 6.0mm

       70: 7.0mm       73: 7.3mm

Ⅳ: Operation force: double-digit

       05: 50gf          07: 70gf

       09: 90gf          10: 100gf

       11: 110gf        12: 120gf

       13: 130gf        15: 150gf

Ⅴ: 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 "1" terminal

      5: DIP, direction of switch function and

          mounting pin is vertical

      6: DIP, direction of switch operation

          and terminal mounting is reverse

Ⅵ: Type of button: single-digit

      0: round

      1: “一” type

      2: “十” type

Ⅶ: Life of product: single-digit

      1: 1M times

      3: 3M times

      5: 5M times

Ⅷ: Derivative code: single-digit

      0: without special items

Ⅸ: Package: single-digit

      0=plastic bag

     1=shrinked plastic package

      2=tape        

      3=tube package  

      4=foam     

      5=undetermined