Pommel cap

The pommel cap was the end-piece of a lightsaber hilt.

Typically, they were made from a single piece of heavy metal, and they also served as the backplate for the inner workings of the lightsaber, completing various circuits. In some lightsabers, the cap also held an extra backup power cell; such was the case with Dooku's lightsaber and Obi-Wan Kenobi's first lightsaber. These heavy ends of the hilt were sometimes incorporated into the fighting styles of a Jedi as an alternative to actually impaling an opponent on the blade end of the weapon. This sometimes provided a nonfatal resolution to an incident.

They typically included a ring to hook onto the wielder's belt when not in use, though some lightsabers, such as Dooku's, used a powerful magnetic plate for the same purpose.

Text and facts from the “Pommel cap/Legends” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.