The CAS Registry Mumber 127346-93-4 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,7,3,4 and 6 respectively; the second part has 2 digits, 9 and 3 respectively. Calculate Digit Verification of CAS Registry Number 127346-93: (8*1)+(7*2)+(6*7)+(5*3)+(4*4)+(3*6)+(2*9)+(1*3)=134 134 % 10 = 4 So 127346-93-4 is a valid CAS Registry Number.