The CAS Registry Mumber 595-00-6 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 5,9 and 5 respectively; the second part has 2 digits, 0 and 0 respectively. Calculate Digit Verification of CAS Registry Number 595-00: (5*5)+(4*9)+(3*5)+(2*0)+(1*0)=76 76 % 10 = 6 So 595-00-6 is a valid CAS Registry Number.