QUOTE(Death Grunty @ Jun 21 2011, 18:16)

Level it to at least 34. Then you'll find out its base duration. Which is either 2.5 or 3.0.
Big difference. (3.0 makes all the difference until 320.)
Ah well, I raised that katana, and it turns proc duration turns to 4 at lv.34 or 35.
So it's a base 3.0 katana.