This was made for measuring wall angles and tracing angle lines onto wood or tiling. For example, to measure angles of a number of odd walls in our house so I could create shelves for some unique little nooks.
In short every tick is 15 deg increments apart, small and large combined. However, the large ticks are 45 deg increments apart.
See example pictures for a visualization of degree examples.
Every part is "elephant's foot" immune, with one caveat. That is when an FDM printer squishes more than normal, which can cause tolerance issues. If the nut is hard to put on one way just flip it upside down and screw on with the side that was not printed on the bed.
The tighter the nut is screwed on the stiffer it moves, which can be nice when using for tracing.