These are all double-sided counters.
The front is the full strength side, while the back is a partial strength. It has all the numbers needed to play the miniatures game on the counters.
To create a unit counter, I take a picture of the figure type, modify the picture to make it easier to print out (take out background, etc) and use that for the main picture of the counter.
I print them out on full sheet labels, then cut and put that on cardboard.
It is easy to make double-sided counters, you just have to be sure that the back-side is a mirror image of the front (so when you past the back sheet on, it matches the units on the front).
Here is an example of a 1/2" sheet, both front and back. I cut the two halves out and mount on appropriately thick cardboard and Voila ! Double sided counters.