Old Navy polo sports Built in flex blue short sleeve shirt size large

Old Navy polo sports Built in flex blue short sleeve shirt size large Condition: New with tags BUT there is a mark on the back of the shirt as seen in the photo. In my opinion it is a faint mark. The shirt has not been treated or washed. Tags: old navy, polo, sports shirt, blue shirt, blue, solid, career, business casual, uniform, uniform shirt, muscle shirt,