Canadian WW2 tank crew helmet.
This helmet shows signs of wear and retains the original web suspension.
It is made of cloth covered cork, with rubber vents in the sides.
A leather “scrum” (not included), attached by laces and buttons, held the head phones.
These helmets provided no ballistic protection, and served purely to prevent head injuries within the tank. 
 
 
Some 12,000 were made. Known in Canadian service as the Helmet, Crash, Tank Battalion, they were not issued overseas, but remained in service in Canada until 1966.
This is a rare item.