Date Shuriken



Derivations
伊達 has many derivations and connotations in Japanese, but in the context of ninja weaponry this almost certainly refers to the Date Clan (伊達氏), particularly Date Masamune (伊達政宗), a 17th century feudal lord of Sendai, and his Kurohabakigumi (黒脛巾組), a Ninja military unit he founded. (Wikipedia) 伊達手裏剣