The CAS Registry Mumber 16320-48-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,6,3,2 and 0 respectively; the second part has 2 digits, 4 and 8 respectively. Calculate Digit Verification of CAS Registry Number 16320-48: (7*1)+(6*6)+(5*3)+(4*2)+(3*0)+(2*4)+(1*8)=82 82 % 10 = 2 So 16320-48-2 is a valid CAS Registry Number.