The CAS Registry Mumber 60437-28-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,0,4,3 and 7 respectively; the second part has 2 digits, 2 and 8 respectively. Calculate Digit Verification of CAS Registry Number 60437-28: (7*6)+(6*0)+(5*4)+(4*3)+(3*7)+(2*2)+(1*8)=107 107 % 10 = 7 So 60437-28-7 is a valid CAS Registry Number.