Bolt +1

Bolt +1 is an enchanted bolt which can harm enemies immune to normal weapon and missiles. They have a +1 bonus to damage and thaco when compared to normal bolts.

In-game description
"Quarrels or bolts are the ammunition fired by crossbows regardless of the weapon's size.  However this bolt has been imbued with a small amount of magical properties which enhances performance in flight, almost as if the bolt was guided towards its target."

Baldur's Gate

 * Thunderhammer Smithy
 * High Hedge Estate
 * Sorcerous Sundries
 * Erdane, a merchant at Durlag's Tower.
 * Ulgoth's Beard Inn