OneTigris Tactical Military Mesh Cap Outdoor Baseball Hat Adjustable Camping Hunting Hat The mesh material on the back, great in providing a bit more flex in the fitting Made of poly-cotton, it comes with 2 air vent holes 3 Loop Panels: a 2"x3" panel on front, a 1"x4" strip on the back and a 1"x1" on the top This summer mesh cap has a hook-and-loop closer for tightening, Head Circumference: 56-60cm (Adjustable) Great for camping, hiking, hunting, baseball, etc.