Shobo

A shobo is a weapon, similar to the Emei piercer of China, which was used by the ninja of Japan for striking pressure points on an opponent. It was a piece of wood that was gripped by the wielder and was hung by a ring worn on the middle finger. Some versions were rings with a wooden peg attached on top. The ends were exposed and were usually sharp which made them effective for paralyzing and even killing enemies quickly and without leaving a trace. They were easily hidden in the ninja's fists and were very lightweight and portable. They were usually worn in pairs. Many Ninjas constructed their own shobo, although some were given from sensei to student.