Dagger +3

Dagger +3 is an enchanted weapon able to inflict 1d4 +3 points of damage and it has -3 THAC0 bonus. The weapon weighs less than 1 lbs and it has a speed factor of 0. This item appears in Baldur's Gate II: Throne of Bhaal and Baldur's Gate II: Enhanced Edition. It can be bought from the Tankard Tree and the merchants Karthis al-Hezzar and Carras sell it.

In-game description
"The typical dagger has a pointed, double-edged blade, as opposed to a knife which has a single edge and is a bit shorter. This particular dagger is magical, having special bonuses to its speed, accuracy, and damage it causes. Also, since it is magical, is it capable of striking opponents that are immune to normal weapons, such as vampires, elementals and mummies."