The frog-mouth helm (or Stechhelm meaning "jousting helmet" in German) was a type of great helm, appearing from around 1400 and lasting into the first quarter of the 16th century.[1] The helmet was primarily used by mounted knights for tournaments (jousting) rather than on the battlefield.[2]
The frog-mouth analogy was drawn from the way the ocularium (the slit through which the wearer of the helm could see) resembles the open mouth of a frog. During jousting tournaments, the helmet offered a better degree of protection from lances that would splinter after impact with the rival's body armour. Early examples of the stechhelm were made from a single piece of metal, while later dated helmets had hinged constructions that could be disassembled.