The CAS Registry Mumber 67106-41-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,7,1,0 and 6 respectively; the second part has 2 digits, 4 and 1 respectively. Calculate Digit Verification of CAS Registry Number 67106-41: (7*6)+(6*7)+(5*1)+(4*0)+(3*6)+(2*4)+(1*1)=116 116 % 10 = 6 So 67106-41-6 is a valid CAS Registry Number.