Charges:

From UOGuide

Charges is generally a term to describe how many uses an item has remaining. Usually found on jewelry, if for example a ring with invisibilty charges has 9 charges then it may be used 9 times before the charges are exhausted.

Charges differ from Durability in that they usually render the item inert when reaching zero, while a zero Durability means the item is about to be destroyed from wearing out, such as armor or weapons.