"Seisan" is thought to be one of the oldest "kata", being quite spread among other Nahate schools. Shito-Ryū has its own version similar to "Sanchin" and different versions are now practiced even in Shuri-te derivatives like Shotokan (called "Hangetsu") and in Wado-Ryū (called "Seishan"). Isshin-ryū also adopted this "kata". Korean Tang Soo Do adopted it, and it is called either by its original name "Sei-Shan" or "Seishan", or by "Ban Wol" which is the Korean translation of "Hangetsu" ("half moon"). Due to its difficulty, this "kata" is often reserved for advanced Tang Soo Do students.