I would say technical t-shirts or soft t-shirts (basically the same). Not technical like most running shirts, which are more mesh, but closer to a really soft cotton feel.
Also, is is possible that they be in BA-Baby Blue?
We were shooting them out of a t-shirt canon in Rosslyn. It seems that people like them though, so we might think about getting a batch made up and seeing if we can selling them at the County building or at a LBS.
What do you guys think about cotton vs. tech fabric?