The CAS Registry Mumber 349496-04-4 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 3,4,9,4,9 and 6 respectively; the second part has 2 digits, 0 and 4 respectively. Calculate Digit Verification of CAS Registry Number 349496-04: (8*3)+(7*4)+(6*9)+(5*4)+(4*9)+(3*6)+(2*0)+(1*4)=184 184 % 10 = 4 So 349496-04-4 is a valid CAS Registry Number.