Can we use all 4 of the colors listed on the Navy shirt? or only 3 as stated?

Sure. I'm looking for a Navy T-shirt with white, medium gray and neon green ink, but if want to add a 4th ink color that's fine.

Ok. I saw you had a Royal blue color, Wasn't sure if that was the shirt color or a 4th. Ill revise my submissions. I think a 4th color would be more appealing...Thx.