The CAS Registry Mumber 63399-02-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,3,3,9 and 9 respectively; the second part has 2 digits, 0 and 2 respectively. Calculate Digit Verification of CAS Registry Number 63399-02: (7*6)+(6*3)+(5*3)+(4*9)+(3*9)+(2*0)+(1*2)=140 140 % 10 = 0 So 63399-02-0 is a valid CAS Registry Number.