70's M type trucker cap.
The front panel is designed to be shallower than the regular M type, and the back panel is deep so that it is easy to wear.
A thick sponge is used for the front panel, which is an extension of the mesh cap, and the washed cotton weather fabric is thin and has a nice texture.
It is a design that can be adjusted with a belt on the back.
Also In Khaki here
Customs/Duty Paid For UK Customers