Mace +2

Mace +2 is an enchanted weapon. When it's compared to a normal mace, the weapon deals +2 points more damage, has -2 THACo bonus, a speed factor 2 points lower and it weighs 1 lbs less. This item appears in Baldur's Gate II: Shadows of Amn and Baldur's Gate II: Enhanced Edition.

It can be bought from the Adventurer's Mart and Karthis al-Hezzar.

In-game description
"The mace is a direct descendant of the basic club, being nothing more than a wooden shaft with an iron head mounted on the end. The shaft of this magical mace seems to guide the wielder, becoming an extension of his hand."