Ⅰ: Code of product series: three-digit

     151: series 151 push switch

Ⅱ: Type of shell: double-digit

      01: Type A shell      02: Type B shell

     03: Type C shell      04: Type D shell

Ⅲ: Loop specification: Single-digit

      1: 1P1T        2: 1P2T

      3: 2P1T     4: 2P2T

Ⅳ: Mechanism of Product: single-digit

      0: product with self-locked function

      1: without self-locked function

Ⅴ: Color of button: single-digit

      0: blackt     1: white

      2: green     3: red

      4: grey       5: french grey

Ⅵ: Type of button: single-digit

      0: round

Ⅶ: Type of terminal: single-digit

      1: PCB terminal (Type A)

      2: PCB terminal (Type B)

      3: PCB terminal (Type C)

      4: soldering terminal (Type A)

      5: soldering terminal (Type B)

Ⅷ: Derivative code: double-digit

Ⅸ: Package: single-digit

     0=plastic bag        1=shrinked plastic package

     2=tape package    3=tube package 

     4=foam package   5=undetermined