Description Commonly Used on models: 488 488 S/N: C57220001001 - C57220999999 488P S/N: C54820001001 - C54820999999 491s S/N: C36312001001 - C36312999999 491s S/N: C36413001001 - C36413999999 CS-490 S/N: C34312001001 - C34312999999 CS-490 S/N: C34413001001 - C34413999999 CS-500P S/N: C19312001001 - C19312999999 CS-500P S/N: C19413001001 - C19413999999