100% cotton. Lightweight.

Kevin Kisner's 1st event on the PGA Tour was in 2011.
Before that he played some mini-tours. This shirt is likely from that era.
Few pros had Bobby Jones contracts and most were famous with big name sponsors. Kisner is from S. Carolina and so is Cerulean Aviation, a small company. 
IMI is a small consulting firm in North Carolina. 

Measurements in inches:
Chest 46
Length 30
Shoulders 23

Refer to last pix, A, D, & E.