In order to use this tool, first you need a program that computes planets' positions in declination. I will put up probably soon an online tool that will calculate it. But all astrology programs offer this function.
I just tried it in mundane astrology for the chart of Israel and I found that the Moon of Israel is at 24n08 by declination. Using this online tool, it gives:
So, we learn that 24n08 is out of bounds, because it's greater than 23n27, the ecliptic limit. Therefore there's a mirroring on the other side of this threshold, at 22n45 (codeclination).
And there're equivalent longitudes for the given codeclination. (actually they represent the Sun's longitude when at 22n45 by declination).
We have two hotspots for the Moon in the Israel chart at 16Gem41 and 13Can18, like two places of hiden influence (similar to antiscia). And we notice that one of these hotspots is actually exactly conjunct with the US Sun at 13Can19 (Sibly chart). This is an extraordinary find, explaining the tight connection between Israel and the US, why Israel is so intimately supported by the US.
Similarly, there might be connections within a natal chart, in synastry between real people or events (as shown above) and there're surely many other ways to use it.