Oh, i didnt know that, thanks Chuck. That clears up the "crew neck" question ^^
I found this in the official rulebook
: (2) All players must wear a shirt covering their upper chest area. A well-tailored shirt with a fold-down, mock turtle, v-neck, crew neck, Henley, or zippered collar, and with sleeves covering the part of the arm from the shoulder to the elbow (commonly known as the upper arm), shall be considered acceptable.
Seems like quite a few collar tipes are allowed. I'd need a picture of every one of them to check if i even have a shirt that would be PDGA approved. When i google these collar cuts, i get so many results showing so many different shapes that it is more confusing than helping.
http://en.wikipedia.org/wiki/Collar_%28clothing%29 does not help that much either. Are there PDGA approved shirts available at PDGA tournaments that require you to wear them ?