Sandogu were the three implements used by the police of the Shogunate to arrest people. They consisted of the sodegarami or 'sleeve tangler', the tsukubo and the sasumata. The aim was to restrain the individual, who might be wielding a sword, so that he could then be more easily disarmed or dealt with. The implements were mounted on poles equipped with spines and barbs along their length, in order to prevent the person that they were attempting to arrest grasping the shaft and wresting the implement away from the arresting officer.
Sandogu are getting scarce these days.
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