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A Suntetsu is a metal rod/spike about 6 inches in length with a ring attached to it. The middle finger is inserted into the ring and the Suntetsu rests in the hand by various grips. Suntetsu are small, easy to conceal and relatively simple to learn how to use. Suntetsu are used for stabbing, poking, pinching, striking, smashing, scraping and throwing. You can use a single Suntetsu or a pair.