Shuriken, also knows as throwing stars, are the most popular weapon used in Ninjutsu.
They were used as a secondary weapon to the sword, and were not generally considered to be a killing weapon.
Shuriken stars were commonly used to slow down attackers or used as a distraction. There is even evidence that ninjas sometimes partially buried throwing stars in the ground as a way to maim their attackers when stepped on.
These Wave shuriken, constructed of steel, measure 3 1/4 inches in size and come in chrome or black finish.