Exploding Sphere

The is a ninja tool stored within Tenten's large scroll. It is a metal sphere with kunai welded onto it and a hidden explosive tag attached to it. It explodes upon contact, sending kunai and fragments of the sphere flying out as shrapnel.

Trivia

 * While unnamed in the anime and manga, it is named in Naruto Shippūden: Ultimate Ninja 4.
 * In episode 307, an unidentified Kumo-nin, who was reincarnated by Kabuto, used similar bombs (though they were spikier and had no explosive tag on the outside).