An Offer from Taerom (aka "A New Suit of Armor") is a side quest in Baldur's Gate and Baldur's Gate: Enhanced Edition that you can undertake after acquiring an Ankheg Shell. Take the shell to Taerom Fuiruim at his shop in Beregost and he will offer to buy it from you. You can sell it for 500 gold, or if you refuse his initial offer you can get a nice set of custom Ankheg Plate Mail armor made (but can only do this once). This will cost you 4,000 gold and will take 10 days to forge (three days in BG:EE). In the Enhanced Edition, you can pay 6,000 gold to get it done in one day. Whether or not you have him make the armor you can bring more shells for additional gold.