Any addons for precise grids on objects?

Been looking at Fluent, and like the way it creates a grid on surfaces.
However, the grids seem to be divisions of the surface rather than being based on real-world increments.

For example, I have a 55cm cube, and want to be able to put a 5mm grid on the surface.

Are there any plugins that can do this?

thanks!

In Fluent you can change the grid-resulotion. Plus some maths, you can have your grid.

Understood - however, this makes it more difficult if, for example, we have an irregularly shaped surface, or a fractional size, and need a precise grid dimension.

Ok, do not really know what you want (a picture would be nice).
Maybe in edit mode, the viewport overlays could help.

Grid Modeller maybe?