These leather gloves are imbued with the darkfire power of the drow.
Hands Slot 4,200 gp
When you hit an enemy with your darkfire racial power, your eladrin and elf allies gain a +2 bonus to damage rolls against that enemy until the end of your next turn.
Power Encounter (Minor Action)
While you have a drow ally within 10 squares of you, you can expend your elven accuracy racial power or your fey step racial power to use the darkfire racial power (Forgotten Realms Player's Guide, page 8).
Published in Adventurer's Vault 2, page(s) 132.