SATO CL4NX Programming Reference Manual page 165

7. All character barcode have the same height when printing UPC-A specifying <D> and then <font>. The first and the
last character barcode have the same height to the guard bar when printing UPC-A specifying <BL> and then
<font>.
When printing UPC-A specifying <D> and <font>, HRI can be printed under the first digit and the last digit because
the height of the first digit and the last digit of the barcode is low. When printing UPC-A specifying <BL> and <font>,
the height of the first digit and the last digit of the barcode is high, and the font interval is narrower than previous
case.
Guard bar
Character barcode
First digit
UPC-A specifying <D> + <font>
Guard bar
Character barcode
Last digit
157
Guard bar
Character barcode
First digit
UPC-A specifying <BL> + <font>
Guard bar
Character barcode
Last digit