The CAS Registry Mumber 63176-93-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,3,1,7 and 6 respectively; the second part has 2 digits, 9 and 3 respectively. Calculate Digit Verification of CAS Registry Number 63176-93: (7*6)+(6*3)+(5*1)+(4*7)+(3*6)+(2*9)+(1*3)=132 132 % 10 = 2 So 63176-93-2 is a valid CAS Registry Number.