The Dharmachakra Kabuto Helmet.
“The Wheel of Dharma kabuto is a form of “kawari-kabuto”—a family of helmets featuring fantastical designs. This helmet features a red-lacquered front crest of an ancient Buddhist symbol depicting the eight-fold path to nirvana. This holy image represents spiritual enlightenment attained by casting off one’s worldly desires, and also holds the power to banish evil.
However, some claim this is not a Wheel of Dharma at all, merely a replica that looks as though it belongs on a device to regulate steam… Some have gone so far as to suggest renaming it to “Valve Kabuto,” but why anyone would make a helmet featuring a valve is unclear…”