Can someone describe or draw a figure 4 fitting for me

I've been around awhile and never heard of a "figure 4 fitting". Where did you get a nomenclature such as this? Double "Y" perhaps?

Sounds like a reference to a drawing for a specific project where the draftsman drew details of some particular fittings and applications and labeled the details as Figure 1, Figure 2 etc.
Then, folks on the project started referring to the item identified in Figure 4 as a Figure 4 fitting, and are still using the term on other projects, erroneously.
I could be wrong.