The Y Size box contains the printer command which sets the rectangle height.
For the Diconix 150 Plus printer, the Y Size box is empty.
For the HP LaserJet IIP printer, the Vertical Rectangle Size command (ESC*cnB) specifies the rectangle's height in 1/300 inch units. The argument n specifies the number of units.
To specify the Vertical Rectangle Size command, type the following in the Y Size box:
\x1B*c%dB