Zebra Technologies R-140 - Manual (Page 20)

Non-Continuous Black Mark Media
Non-continuous black mark media has black marks printed on the back that
indicate the start and end of each label (refer to Figure 3).
Continuous Media
Continuous media (refer to Figure 4) is one uninterrupted roll of material
that allows the image to be printed anywhere on the label.
Zebra R-140 User’s Guide 11
Non-continuous media for black mark sensing
Black mark
Black mark
Figure 3
Continuous media (no gaps, holes, notches, or black marks)
Figure 4