The CAS Registry Mumber 1430-26-8 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,4,3 and 0 respectively; the second part has 2 digits, 2 and 6 respectively. Calculate Digit Verification of CAS Registry Number 1430-26: (6*1)+(5*4)+(4*3)+(3*0)+(2*2)+(1*6)=48 48 % 10 = 8 So 1430-26-8 is a valid CAS Registry Number.