Kyokushin Sai Deco. Great for any dojo or temple decoration. Thanks to my friend smilewithtears for making the Sai wall decoration mesh. Comes with a beautiful Kanku and Kanji in red. Arigatou Gozaimasu! No poses. Try it before you buy! Please Leave Reviews Below And Concerns On My Page. "Osu no Seishin". The sai is a traditional martial arts weapon. The basic form of the weapon is that of a pointed, prong shaped metal baton, with two curved prongs called yoku projecting from the handle. It is generally used in pairs. There are many types of sai with varying prongs for trapping and blocking.