Here is an awesome Vintage 1990's Polo By Ralph Lauren Flag Henley Pull Over Collar Shirt, this is a great Patriotic look. Would be awesome for 4th of July. All tags are attached and it states a size S but modern measurements are listed below.

This is a vintage used item and is in good vintage used condition with little to no wear, there are no rips, tears, holes or smells. It is 100% Cotton

Measurements
Shoulder to shoulder = 19 inches
Chest 42
Length = 32 inches