A kettle hat, also known as a war hat, is a type of helmet made of iron or steel in the shape of a brimmed hat. There are many design variations. The only common element is a wide brim that afforded extra protection to the wearer. It gained its common English language name from its resemblance to a metal cooking pot (the original meaning of kettle). The kettle hat was common all over Medieval Europe. This one is a 15th century model.