Helmet is a device to protect the head, a hat worn by soldiers during training and combat, and an indispensable tool in people's transportation. It is divided into military helmets, police helmets and civilian helmets. It is mostly semicircular, mainly composed of shell, lining and suspension device. The shell is made of special steel, glass fiber reinforced plastic, reinforced plastic, leather, nylon and other materials to resist the head damage caused by warhead, shrapnel and other striking objects.

Helmets can be traced back to ancient times. In pursuit of wild animals and fighting, primitive people used coconut shells and other fibrous materials as well as armadillo shells and turtle shells to protect their heads. To stop the attack. Later, with the development of metallurgical technology and the need of war, the metal helmet was invented. The earliest metal helmet abroad is the bronze helmet made around 800 BC.

Source: @jesstfang