The CAS Registry Mumber 26733-60-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,6,7,3 and 3 respectively; the second part has 2 digits, 6 and 0 respectively. Calculate Digit Verification of CAS Registry Number 26733-60: (7*2)+(6*6)+(5*7)+(4*3)+(3*3)+(2*6)+(1*0)=118 118 % 10 = 8 So 26733-60-8 is a valid CAS Registry Number.