This is a clean and simple -- essential-- Valor tee.
 
For the adult sizes, it's printed on a brand we haven't used before (AS Color in the box fit). It's supposed to be a bit of a shorter and boxier fit and it also comes in a men's and women's cut. The women's cut is about 4 inches shorter than the men's cut. 
 
For the youth sizes, it's printed on the AS Color staple youth tee and comes in Navy (instead of black) and white.