To product a SSCC-18 barcode you need to call SSCC18 function (in FontPal and in your program).
To calculate the font size, first find out the X dimension: here is 0.02" = 20 mils.
From font spec table
http://www.morovia.com/fonts/code128/, technical specification tab, our Code128 fonts produces barcodes X dimension 6.78 mils at 10 points.
Therefore to achieve 20 mils, font size should be 20.0/6.78 * 10= 30 points.
At 30 points the M fonts produce bar height at 30/10 * 0.42 = 1.26 inch, which satisfy home depot requirement.
Recommended Font :
MRV Code128Msize :
30 points.
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