The CAS Registry Mumber 12006-41-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,2,0,0 and 6 respectively; the second part has 2 digits, 4 and 1 respectively. Calculate Digit Verification of CAS Registry Number 12006-41: (7*1)+(6*2)+(5*0)+(4*0)+(3*6)+(2*4)+(1*1)=46 46 % 10 = 6 So 12006-41-6 is a valid CAS Registry Number.