This is not a vintage item.
 
Hat, Sun, Hot Weather, Type II (boonie hats) available in Sand, Olive Green and Woodland.
100% rip-stop cotton.

Available in Small, Medium, Large and X-Large.

Approx size chart:
Small 54-55 cm
Medium 56-57 cm
Large 58-59 cm
X-Large 60-61 cm