Mengu (Japanese facial armour)

Mempo (also menpō, mengu or occasionally men yoroi), is the term for various types of facial armour worn by the samurai class and their retainers in feudal Japan. Types of Japanese facial armour include the somen, menpō, hanpo and happuri.

Mempo were facial armour which covered all or part of the face and provided a way to secure the top-heavy kabuto (helmet). The Shinobi-no-o (chin cord) of the kabuto would be tied under the chin of the mempo. There were small hooks called ori-kugi or posts called odome located on various places to help secure the kabuto's chin cord. Mengu may be constructed from iron or leather, or a combination of both. They may have a lacquered or rusted type of finish and can include a variety of facial details, such as moustaches, fierce teeth and a detachable nose. Most mempo with the exception of the happuri had a small hole underneath the chin for sweat drainage.

Mempo are similar to masks worn by armored cavalry and infantry in ancient Chinese armies from the Han Dynasty to the Song Dynasty.

Somen covered the entire face.

Menpō covered the face from the nose down to the chin.

Hanbo covered the lower face from under the nose to the chin.

Happuri covered the forehead and cheeks.

Odome, an attachment post for securing the chin strap of a kabuto (helmet).

Ori-kugi, an attachment hook for securing the chin strap of a kabuto (helmet).

Ase nagashi no ana, a drain hole (or tube) for perspiration located under the chin of various mengu.

Yodare-kake, throat guard on various mengu.

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