The Swiss M1918 helmet (also known as M18) combat helmet

The Swiss M1918 helmet (also known as M18) is a steel military combat helmet used by Switzerland from its introduction in 1918 to its replacement by the M1971. In 1943 improvements would be made to the design to which it would be called the M1918/40. The helmet would be seen used by Swiss servicemen until the late 20th century.

M18 is a Swiss-made steel helmet which was was issued from the end of WWI through to the 1930’s. In 1940, the helmet was updated with a 3/4 ring liner (opposed to a full ring) and this became known as the M18/40. Then in 1944 all helmets were withdrawn and had a sawdust mixed matte black paint applied over the original. This is what you see here.