Screw, #8x1-1/4" PH Flat Tap (241, 251, 361, 2411,
          2511, 2711, 2811, 3211, 430, 430-2,
          500 Series, 600 Series)
    NOTE: IF USING THIS SCREW FOR REAR DUCT, SEE
          SERIAL # BREAKS BELLOW. FOR ALL OTHER
          APPLICATIONS, DISREGARD SERIAL # BREAKS.
 200/300   Use Regardless of Serial Number.
430/430-2  Use Regardless of Serial Number.
  511      Use Starting with #M1004775 & between
           #M964470-M964769. Prior to #M1004775
           except between #M964470-M964769 see
           6200230.
  532      Use Starting with #M/P1004775 & between
           #M964770-M965069 and #M990700-M990999.
           Prior to #M/P1004775 except between
           #M964770-M965069 and #M990700-M990999
           see 6200230.
  542      Use Regardless of Serial Number.
  550      Use Starting with #M/P1004775 & between
           #M964070-M964469 and #M984750-M985149.
           Prior to #M/P1004775 except between
           #M964070-M964469 and #M984750-M985149
           see 6200230.
  561      Use Starting with #M/P1004775 & between
           #M965470-M965869.  Prior to #M/P1004775
           except between #M965470-M965869
           see 6200230.
  590      Use Starting with #M1004775 & between
           #M965870-M966269. Prior to #M1004775
600 Series Use Regardless of Serial Number.